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Human Oral Epithelium (human + oral_epithelium)
Selected AbstractsStrain persistence of invasive Candida albicans in chronic hyperplastic candidosis that underwent malignant changeGERODONTOLOGY, Issue 2 2001DW Williams Abstract Objectives: The aim of this study was to assess persistence and tissue invasion of Candida albicans strains isolated from a 65 year-old patient with chronic hyperplastic candidosis (CHC), that subsequently developed into squamous cell carcinoma (SCC). Materials and Methods: C. albicans (n=7) were recovered from the oral cavity of the patient over seven years. Confirmation of CHC and SCC in this patient was achieved by histopathological examination of incisional biopsy tissue. DNA fingerprinting was performed on the seven isolates from the CHC patient together with a further eight isolates from patients with normal oral mucosa (n=2), chronic atrophic candidosis (n=1), SCC (n=1) and CHC (n=4). Genotyping involved the use of inter-repeat PCR using the eukaryotic repeat primer 1251. Characterisation of the tissue invasive abilities of the isolates was achieved by infecting a commercially available reconstituted human oral epithelium (RHE; SkinEthic, Nice, France). After 24 h. C. albicans tissue invasion was assessed by histopathological examination. Results: DNA fingerprinting demonstrated strain persistence of C. albicans in the CHC patient over a seven year period despite provision of systemic antifungal therapy. The strain of C. albicans isolated from this patient was categorised as a high invader within the RHE compared to other isolates. Conclusions: Candidal strain persistence was evident in a patient with CHC over seven years. This persistence may be due to incomplete eradication from the oral cavity following antifungal therapy or subsequent recolonisation from other body sites or separate exogenous sources. The demonstration of enhanced in vitro tissue invasion by this particular strain may, in part, explain the progression to carcinoma. [source] Adverse effects of Sudanese toombak vs.JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 2 2010Swedish snuff on human oral cells J Oral Pathol Med (2010) 39 128,140 Background:, The high incidence of oral cancer in Sudan has been associated with the use of toombak, the local type of smokeless tobacco. However, its specific effects on human oral cells are not known. We aimed to investigate the effects of toombak on primary normal human oral keratinocytes, fibroblasts, and a dysplastic oral keratinocytic cell line, and to compare them with the effects induced by Swedish snuff. Method:, Aqueous extracts were prepared from moist toombak and Swedish snuff and added in serial dilutions on in vitro monolayer cultured cells. Cell viability, morphology and growth, DNA double-strand breaks (,H2AX staining), expression of phosphatidylserine (Annexin V staining), and cell cycle were assessed after various exposure time periods. Results:, Significant decrease in cell number, occurrence of DNA double-strain breaks, morphological and biochemical signs of programmed cell death were detected in all oral cell types exposed to clinically relevant dilutions of toombak extract, although to a lesser extent in normal oral fibroblasts and dysplastic keratinocytes. G2/M-block was also detected in normal oral keratinocytes and fibroblasts exposed to clinically relevant dilutions of toombak extract. Swedish snuff extract had less adverse effects on oral cells, mainly at non-clinically relevant dilutions. Conclusion:, This study indicates a potential for toombak, higher than for Swedish snuff, to damage human oral epithelium. Dysplastic oral keratinocytes were less sensitive than their normal counterparts, suggesting that they might have acquired a partially resistant phenotype to toombak -induced cytotoxic effects while still being prone to DNA damage that could lead to further malignant progression. [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] IL-1,, IL-1ra and IL-8 are differentially induced by Candida in experimental oral candidiasisORAL DISEASES, Issue 4 2007JAMS Jayatilake Objective:, To investigate the expression of interleukin-1, (IL-1,), IL-1ra and IL-8 by the oral epithelium challenged by various Candida species. Materials and methods:,In vitro candidiasis was induced by C. albicans wild type SC5314, its EFG1, CPH1 and secretory aspartyl proteinase (SAP) mutants and, ATCC isolates of C. albicans, C. tropicalis and C. dubliniensis using a reconstituted human oral epithelium (RHOE) model. IL-1,, IL-1ra and IL-8 levels in culture media were quantified by an enzyme-linked immunosorbent assay at 12, 24 and 48 h. Fungal invasion and IL-1ra expression in RHOE were detected by periodic acid-Schiff staining and immunohistochemistry. Results:, Overall, the invasive Candida induced relatively higher levels of IL-1,, IL-1ra and IL-8 in the culture media than the noninvasive isolates. IL-1, and IL-1ra levels induced by Candida with hyphal invasion were significantly higher (P < 0.05) than those induced by the isolates without hyphal invasion at 12, 24 and 48 h. Candida albicans SC5314 induced IL-1ra expression in RHOE at 12 and 24 h but not at 48 h consistent with its hyphal invasion; while the noninvasive mutants and non- albicans Candida induced IL-1ra expression at 48 h. Conclusions:, The cytokine expression profiles in experimental oral candidiasis may be associated with the invasive potential of Candida. [source] | ||||||||||