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Human Oral Mucosa (human + oral_mucosa)
Selected AbstractsNerve growth factor ,/pro-nerve growth factor and their receptors in normal human oral mucosaEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 5 2007Katsuhiko Hayashi Nerve growth factor , (NGF- ,) and its precursor proNGF are important for the differentiation and survival of neurons and dermal keratinocytes. The aim of this study was to determine the role that NGF might play in the differentiation and wound healing of oral mucosa. Cultured normal human oral mucosal keratinocytes expressed mRNA for NGF- ,/proNGF and for their receptors TrkA and p75NTR. Lysates from cultured oral mucosal keratinocytes did not contain detectable amounts of mature 14-kDa NGF- , but did contain several NGF proforms with molecular weights between 32 and 114 kDa. Culture medium from oral mucosal keratinocytes contained 75 kDa proNGF. The addition of NGF- , significantly enhanced the proliferation of oral mucosal keratinocyte cultures and in vitro scratch closure. Immunostaining of biopsies from normal oral mucosa showed the presence of proNGF in all epithelial layers. NGF staining was observed in the granular and upper spinous cell layers. TrkA immunoreactivity was detected in basal and parabasal cells, with weak to moderate staining in spinous and granular cell layers. p75NTR staining was seen in basal cell layers. These findings indicate that NGF- ,/proNGF have mitogenic and motogenic effects on oral mucosal keratinocytes and therefore may aid in the healing of oral wounds. Differential expression of NGF and NGF receptors throughout the epithelium suggests a role in epithelial differentiation. [source] Antioxidant enzyme levels in oral squamous cell carcinoma and normal human oral epitheliumJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 2 2002J. Yang Abstract Background:, The antioxidant enzymes (manganese- and copper-zinc-containing superoxide dismutases, catalast and glutathione peroxidase) limit cell injury induced by reactive oxygen species. The purpose of the study was to determine whether human oral squamous cell carcinomas have altered antioxidant enzyme levels. This study is the first to undertake this task in human oral mucosa and squamous cell carcinoma. Methods:, Semiquantitative immunohistochemistry was used to examine 26 archived oral squamous cell carcinoma biopsies. Fourteen well-differentiated and 12 poorly differentiated tumors were examined, as were 12 specimens of oral mucosa. All sections were reviewed by two oral and maxillofacial pathologists, and image analysis of the immunostained sections was performed using NIH Image. Antioxidant enzyme staining intensities were compared in the different groups by Duncan's multiple range test. Results:, In general, mucosal basal cells displayed lower antioxidant enzyme levels than spinous cells, and primary tumor cells displayed lower antioxidant enzyme staining intensities than did their normal cell counterparts. Moreover, poorly differentiated tumor cells showed lower antioxidant enzyme staining intensities than well-differentiated tumor cells. Manganese-containing superoxide dismutase staining intensities were, however, higher in well-differentiated oral squamous cell carcinomas than their normal cells of origin. Conclusions:, Detection of antioxidant enzymes may be a useful future marker in the molecular diagnosis of the oral cancer. Moreover, it may be possible to not only monitor the effectiveness of chemopreventitive and therapeutic strategies in oral cancer using these enzymes, but to monitor tumor recurrence. [source] In vitro and in vivo cytokeratin patterns of expression in bioengineered human periodontal mucosaJOURNAL OF PERIODONTAL RESEARCH, Issue 5 2009I. Garzón Background and Objective:, Development of human oral mucosa substitutes by tissue engineering may provide new therapeutic tools for the management of periodontal diseases. In this study we evaluated a fibrin,agarose human oral mucosa substitute both in vitro and in vivo. Material and Methods:,In vitro bioengineered oral mucosa substitutes were developed from irrelevant biopsy samples of human oral gingiva. In vivo evaluation of the constructed tissues was performed by implantation into athymic nude mice. The expression of several epithelial markers was assessed by microarray analysis and immunohistochemistry. Results:, Bioengineered oral mucosa samples kept in vitro developed a multilayered epithelium that expressed several cytokeratins, including some markers of simple epithelia (cytokeratins 7, 8 and 18), along with markers of stratified epithelia (cytokeratins 5 and 13) and of cell proliferation (proliferating cell nuclear antigen). Bioengineered tissues grafted in vivo onto nude mice exhibited very good biointegration with the host, showing a cytokeratin expression pattern that was very similar to that of normal native oral mucosa controls. Histological analysis of the artificial tissues demonstrated that oral mucosa substitutes evaluated in vivo were structurally mature, showing some typical structures of human native oral mucosa such as rete ridges and chorial papillae, along with numerous blood vessels at the fibrin,agarose stromal substitute. These structures were absent in samples evaluated in vitro. Conclusion:, The results indicate that this model of human oral mucosa, constructed using fibrin,agarose scaffolds, shows similarities to native oral mucosa controls and imply that bioengineered oral mucosa substitutes could eventually be used clinically. [source] In vivo experimental model of human gingival mucosa using immunodeficient miceJOURNAL OF PERIODONTAL RESEARCH, Issue 4 2007K. Tsukinoki Background and Objective:, To establish an in vivo experimental model for examining human periodontal tissue, the present study examined several transplant techniques that maintain the structure and characteristics of human gingival mucosa. Material and Methods:, Human oral mucosal tissue samples were collected from the gingiva (n = 11), palate (n = 1), and tongue (n = 3). These mucosal grafts were transplanted onto BALB/c nu/scid mice with double-mutant immunodeficiency. Murine skin, twice the size of the graft, was cut open in an ,,'-shape. Next, the connective tissue side of the graft was placed onto the murine connective tissue. Immunohistochemical analysis was also performed, using polyclonal rabbit antibody to involucrin, monoclonal antibody to vimentin, monoclonal antibody to CD34, and monoclonal antibody to Ki-67, to determine whether the characteristics of human oral mucosa were maintained. Results:, When the connective tissue side of the graft was placed on the murine fascial membrane, the histological structure of the graft was maintained for 60 d. These grafts were examined for human characteristics using human-specific antibodies. Immunohistochemically, the expression patterns of involucrin, vimentin, and Ki-67 indicated that transplanted mucosa revealed normal human characteristics, including differentiation and proliferation up to 80 d. CD34 was not detected in the graft endothelial cells. Conclusion:, The present study revealed that the novel technique of transplantation of human gingival mucosa in nu/scid mice may serve as an in vivo experimental model of periodontal disease. [source] Distribution of Langerhans cells and mast cells within the human oral mucosa: new application sites of allergens in sublingual immunotherapy?ALLERGY, Issue 6 2008J.-P. Allam Background:, Sublingual immunotherapy (SLIT) represents an alternative to subcutaneous immunotherapy. While antigen-presenting cells such as Langerhans cells (LCs) are thought to contribute to the effectiveness of SLIT, mast cells (MCs) most likely account for adverse reactions such as sublingual edema. As little is known about LCs and MCs within the oral cavity, we investigated their distribution in search for mucosal sites with highest LCs and lowest MCs density. Methods:, Biopsies were taken simultaneously from human vestibulum, bucca, palatum, lingua, sublingua, gingiva, and skin. Immunohistochemistry and flow cytometry were used to detect MCs, LCs and high affinity receptor for IgE (Fc,RI) expression of LCs. Mixed lymphocyte reactions were performed to assess their stimulatory capacity. Results:, Highest density of MCs was detected within the gingiva, while the lowest density of MCs was found within the palatum and lingua. However, sublingual MCs were located within glands, which might explain swelling of sublingual caruncle in some SLIT patients. Highest density of LCs was detected within the vestibular region with lowest density in sublingual region. Highest expression of Fc,RI was detected on LCs within the vestibulum. Furthermore LCs from different regions displayed similar stimulatory capacity towards allogeneic T cells. Conclusions:, In view of our data, different mucosal regions such as the vestibulum might represent alternative SLIT application sites with potent allergen uptake. Our data might serve as a basis for new application strategies for SLIT to enhance efficiency and reduce local adverse reactions. [source] Immunohistochemical demonstration of p63 in DMBA-induced hamster buccal pouch squamous cell carcinogenesisORAL DISEASES, Issue 5 2003YK Chen Objectives: Abnormalities in the p53 gene are regarded as the most consistent genetic abnormalities detected in head and neck squamous cell carcinogenesis. Two new members of the p53 gene family, p73 at the 1p36 region and p63 at the 3q27-29 region, have recently been identified. They share considerable sequence homology with p53 in the transactivation, DNA binding, and oligomerization domains, indicating possible involvement in carcinogenesis. To our knowledge, however, p63 expression in experimental oral carcinogenesis has not been studied. Materials and methods: Immunohistochemical analysis of p63 protein expression was performed in 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch squamous cell carcinogenesis. Fifty outbred, young (6 weeks), male, Syrian golden hamsters (Mesocricatus auratus) were randomly divided into three experimental groups (each consisting of 10 3-, 9- and 15-week DMBA treated animals), and two control groups (with 10 animals in each). The pouches of the three experimental groups were painted bilaterally with a 0.5% DMBA solution three times a week. The treatment protocol for animals in one of the control groups was identical with only mineral oil applied, while the other control group remained untreated throughout the experiment. Results: In all of the untreated and mineral oil-treated pouch mucosa, nuclear positivity for p63 was mainly observed in the basal/parabasal cell layers. The p63 nuclear positivity extended from the basal/parabasal layers to the whole epithelial layers in the 3- and 9-week DMBA-treated pouch mucosa. Furthermore, the positive nuclear-stain cells were randomly distributed throughout the entire epithelial layers in the 3- and 9-week DMBA-treated pouch-mucosa specimens. In carcinomas from 15-week DMBA-treated pouch specimens, p63 staining was more uniform and homogeneous for the less-differentiated tumor areas. By contrast, p63 expression was noted mainly in the peripheral cells of tumor nests in the well-differentiated tumor areas. Conclusions: The results of this study are consistent with those from previous analyses of p63 expression in human oral mucosa, suggesting that p63 may be associated with the regulation of epithelial differentiation and proliferation in DMBA-induced hamster buccal pouch squamous cell carcinogenesis. Further study is required to investigate which p63 isoform(s) is/are involved in hamster buccal pouch carcinogenesis. [source] | ||||||||||