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Background

The oral lichen planus is a chronic inflammatory disease. Although its aetiology is not well understood, the role of T lymphocytes in its inflammatory events is recognised. Identifying the epigenetic mechanisms involved in the pathogenesis of this immune‐mediated condition is fundamental for understanding the inflammatory reaction that occurs in the disease. The purpose of this work was to evaluate the methylation pattern of 21 immune response‐related genes in the different clinical forms of oral lichen planus.

Methods

A cross‐sectional study was performed to analyse the DNA methylation patterns in three distinct groups of oral lichen planus: (i) reticular/plaque lesions; (ii) erosive lesions; (iii) normal oral mucosa (control group). After DNA extraction from biopsies, the samples were submitted to digestions by methylation‐sensitive and methylation‐dependent enzymes and double digestion. The relative percentage of methylated DNA for each gene was provided using real‐time polymerase chain reaction arrays.

Results

Hypermethylation of the STAT5A gene was observed only in the control group (59.0%). A higher hypermethylation of the ELANE gene was found in reticular/plaque lesions (72.1%) compared to the erosive lesions (50.0%).

Conclusion

Our results show variations in the methylation profile of immune response‐related genes, according to the clinical type of oral lichen planus after comparing with the normal oral mucosa. Further studies are necessary to validate these findings using gene expression analysis.  相似文献   
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To assess the ingestion of folate and nutrients involved in the 1-carbon cycle in non-treated patients with colorectal adenocarcinoma in a reference center for oncology in southeastern Brazil. In total, 195 new cases with colorectal adenocarcinoma completed a clinical evaluation questionnaire and a Food Frequency Questionnaire (FFQ). Blood samples from 161 patients were drawn for the assessment of serum folate. A moderate correlation was found between serum concentrations of folate, folate intake and the dietary folate equivalent (DFE) of synthetic supplements. Mulatto or black male patients with a primary educational level had a higher intake of dietary folate. Of patients obtaining folate from the diet alone or from dietary supplements, 11.00% and 0.10%, respectively, had intake below the recommended level. Of the patients using dietary supplements, 35% to 50% showed high levels of folic acid intake. There was a prevalence of inadequacy for vitamins B2, B6 and B12, ranging from 12.10% to 20.18%, while 13.76% to 22.55% of patients were likely to have adequate choline intake. The considerable percentage of patients with folate intake above the recommended levels deserves attention because of the harmful effects that this nutrient may have in the presence of established neoplastic lesions.  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - To compare the blood flow situation in primary open-angle glaucoma (POAG) and pseudoexfoliation glaucoma (PXG) using optical...  相似文献   
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Previous studies have investigated the effect of ageing on age estimation from faces as well as the occurrence of an own-age bias in such age estimation from faces. To the best of our knowledge, the occurrence of an own age effect on age estimation from voices has never been examined earlier using an experimental design in which the age of participants (young vs. old) and the age of voice stimuli (young vs. old) were crossed. Results revealed an own-age bias in older adults only. In comparison with younger adults, older participants showed age estimation abilities that are preserved for voices from their own age group and impaired for younger voices. This own age bias was absent in younger participants.  相似文献   
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