Desmoid-type fibromatosis (DF) is a rare mesenchymal tumor occurring in only 2 to 4 people per 1,000,000 population a year. Desmoid tumors are either seen sporadically or in individuals with familial adenomatous polyposis (FAP). The etiology of sporadic DF is uncertain. The aim of this study was to estimate the potential significance of germline mutations in the АРС gene in patients with sporadic DF. АРС exons were amplified, studied using conformation sensitive gel electrophoresis and then Sanger-sequenced. The obtained data were processed in Statistica 10. Mutations were detected in 6 (12%) of 51 participants with sporadic DF. Those 6 patients shared a typical DF phenotype characterized by early age of onset (5.8 years on average, in contrast to the patients without APC mutations, who developed DF at 19 years of age; р = 0.02), severe clinical course, multifocal localization on the trunk, and poor prognosis. All of the detected APC mutations were localized to the 3'-end of the gene. For the purpose of comparison, we analyzed a sample of 12 patients with FAP-associated DF. Of those patients, 6 carried mutations in the APC gene. In the analyzed sample, the patients with FAP and the mutant APC gene developed DF at older age (35 years) than the patients with sporadic DF (p = 0.004) and their tumors were not multifocal. This means that sporadic and FAP-associated desmoids have different phenotypes in patients with APC mutations. Patients with sporadic tumors have mutations at the 3'-end of the АРС gene more often than individuals with FAP-associated DF. To our knowledge, this is the first study to characterize the subtype of sporadic desmoid fibromatosis phenotypically determined by germline mutations in the APC gene.
VIEWS 4472
DNA quantification is a routine yet important procedure that determines the efficacy of long-term sample storage and further manipulations with the sample. There are a few well-established methods for measuring DNA concentrations. However, it still not fully clear how concordant their results are. The aim of this work was to measure DNA concentrations in a set of samples using different quantification methods and to compare the obtained values. In 2 independent experiments, a total of 100 genomic DNA samples were analyzed using 3 different DNA quantification methods, including spectrophotometry (NanoDrop), fluorometry (Qubit) and real-time PCR (Quantifiler). The obtained relative concentrations demonstrated an excellent correlation (the correlation coefficients were as high as 0.98 to 0.99). However, the absolute concentrations showed a considerable variation and even a twofold difference. Spectrophotometry yielded the highest concentrations, whereas fluorometry yielded the lowest. The real-time PCR results were intermediate. The differences were more pronounced for the samples with low DNA concentrations. We recommend that such differences should be accounted for when estimating DNA concentrations using an arsenal of different quantification methods.
VIEWS 4740
Generalized chronic periodontitis (GCP) is a widespread disease. It has a serious negative impact on the quality of a patient’s life, posing a challenge to dentists all over the world. At present, standard therapy regimens for GCP adopted in the Russian Federation do not account for the mucosal barrier state, which is determined by a number of various factors, including the levels of secretory immunoglobulin A (sIgA). In our study, we attempted to assess the functional state of the mucosal barrier in patients with GCP and to provide a rationale for using immunotherapy aimed at restoring the effective barrier function of the oral mucosa. SIgA concentrations, which served as an indicator of the mucosal barrier state, were measured with ELISA. We found that patients with GCP had significantly lower sIgA concentrations in the oral fluid in comparison with healthy individuals. Although therapeutic procedures did help to increase sIgA levels, they still were much lower after therapy than in healthy volunteers (54.6 ± 30.5 µg/ml vs 151.2 ± 105.2 µg/ml). Increased permeability of the mucosal barrier caused sIgA to leak into the peripheral blood serum, where its concentration grew from 0.21 ± 0.28 µg/ml to 0.35 ± 0.47 µg/ml during the treatment course, suggesting damage to the mucosal integrity. This fact needs to be accounted for when treating patients with GCP.
VIEWS 4811