Fatty acid-related modulations of membrane fluidity in cells: detection and implications.

Metabolic homeostasis of fatty acids is complex and well-regulated in all organisms. The biosynthesis of saturated fatty acids (SFA) in mammals provides substrates for ß-oxidation and ATP production. Monounsaturated fatty acids (MUFA) are products of desaturases that introduce a methylene group in cis geometry in SFA. Polyunsaturated fatty acids (n-6 and n-3 PUFA) are products of elongation and desaturation of the essential linoleic acid and α-linolenic acid, respectively. The liver processes dietary fatty acids and exports them in lipoproteins for distribution and storage in peripheral tissues. The three types of fatty acids are integrated in membrane phospholipids and determine their biophysical properties and functions. This study was aimed at investigating effects of fatty acids on membrane biophysical properties under varying nutritional and pathological conditions, by integrating lipidomic analysis of membrane phospholipids with functional two-photon microscopy (fTPM) of cellular membranes. This approach was applied to two case studies: first, pancreatic beta-cells, to investigate hormetic and detrimental effects of lipids. Second, red blood cells extracted from a genetic mouse model defective in lipoproteins, to understand the role of lipids in hepatic diseases and metabolic syndrome and their effect on circulating cells.

The presence of Helicobacter pylori in dental plaque of children and their parents: is it related to their periodontal status and oral hygiene?

AIM: To investigate the possible presence of H. pylori in subgingival dental plaque of children with upper gastrointestinal symptoms, as well as of their parents' and to detect any association between the presence of H. pylori and oral hygiene together with the periodontal status of children and their parents. MATERIALS AND METHODS: The study comprised of 35 children with upper gastrointestinal symptoms, aged 4 to 14 years and 45 family members (mothers and/or fathers). Gastric biopsies were collected from all children for CLO-test, histology and culture. Serology was used to assess the H. pylori infection status of their parents. Before endoscopy, subgingival dental plaque from children and their parents were collected from 4 healthy and 4 diseased sites, and the clinical indices (gingival index, plaque index, bleeding on probing, pocket depth, loss of clinical attachment) after plaque collection were recorded. STATISTICS: The Chi-square test was performed to investigate possible differences between children and their parents and logistic regression analysis was used to evaluate the association of parental infection status with that of children. RESULTS: 15 out of 35 children (42.86%) were found H. pylori-positive. In 6 out of the 15 infected children (40%) H. pylori was also identified in their subgingival plaque samples, as well as in one among the 20 non infected children. The presence of H. pylori in dental plaque was significantly associated with its presence in the gastric antrum (p=0.0274). H. pylori was identified in the dental plaque of 7 mothers corresponding to children with positive PCR in their dental plaque and of 4 fathers (one corresponding with his child found H. pylori positive in dental plaque). Children who had H. pylori identified in their dental plaque belonged to families with members also having H. pylori in dental plaque. No significant relationship between periodontal clinical parameters and detection of H. pylori in dental plaque in both children and their parents was found. However, the presence of H. pylori in the subgingival plaque samples was significantly correlated with the parental diseased sites (p=0.02). CONCLUSION: H. pylori was detected in subgingival dental plaque of children and their families, possibly acting as a "reservoir" contributing to the intra-familial spread. Efficient oral hygiene and healthy periodontal status could reduce this transmission.

Oral hygiene and periodontal treatment needs in children and adolescents with coeliac disease in Greece.

AIM: To evaluate the factors that influence the oral hygiene and the periodontal treatment needs of children and adolescents with coeliac disease (CD) in Greece. METHODS: The sample consisted of 35 children and adolescents, aged 4-18 years. The evaluation included consideration of the detailed medical history, the duration of CD and of gluten-free diet, the history of oral mucosal findings and a dental questionnaire that included information about oral hygiene habits, symptoms of periodontal disease and dental attendance. The clinical dental examination consisted of the simplified gingival index, the oral hygiene index and the periodontal screening and recording index. STATISTICS: The chi square and logistic regression analysis were performed in order to determine the factors or parameters that had a statistically significant (p ≤ 0.05) impact on oral hygiene and periodontal treatment needs of children and adolescents with CD. RESULTS: The periodontal treatment need of children and adolescents with CD were high and most of them needed treatment of gingivitis (60.01%) and only a few subjects had a healthy periodontium (34.29%). The periodontal treatment need index, the simplified gingival index and the hygiene index correlated statistically significantly with the presence of a coexisting disease, frequency of tooth brushing, bleeding upon brushing and oral malodor. CONCLUSION: The periodontal treatment need of children and adolescents with CD correlated with factors that related to the presence of a second medical condition and to the personal oral hygiene habits. Additionally, the oral hygiene level and periodontal status of children with CD do not have any specific characteristics but they have similarities to the oral hygiene level and periodontal status of the children of the general population.

Measurement of both native and inactivated forms of alpha1 proteinase inhibitor in human inflammatory extracellular fluids.

BACKGROUND: Inactivation of the elastase inhibitor, alpha1 proteinase inhibitor (alpha1PI), may be of pathogenic significance in inflammatory diseases like periodontal disease. Two key mechanisms of inactivation appear to be (a) the formation of an alpha1PI-elastase complex and (b) proteolytic cleavage by elastase or other enzymes such as metalloproteinases of host origin or enzymes of bacterial origin. Based on the different heat stabilities of the intact, complexed and proteolytically cleaved forms of alpha1PI, an enzyme-linked immunosorbent assay (ELISA) that allowed the simultaneous measurement of native and inactive forms of alpha1PI was developed. METHODS: The ELISA method described employs a commercially available antibody and represents a rapid, reproducible and sensitive method for studying alpha1PI inactivation in human inflammatory diseases. The assay was applied to normal human plasma and to human extracellular fluids obtained from patients with inflammatory diseases such as adult periodontitis and rheumatoid arthritis. Samples from patients with osteoarthritis, a "non-inflammatory" joint disease, were also studied. RESULTS: The findings expressed as the mean percentage (+/-SD) of the total alpha1PI that was inactivated were as follows: gingival crevicular fluid from adult periodontitis patients: 73.5+/-16.6% (n=12); normal human plasma: 8.4+/-4.9% (n=13); knee-joint synovial fluid (SF) from rheumatoid arthritis patients: 12.5+/-4.5% (n=15); plasma from rheumatoid arthritis patients: 8.0+/-1.8% (n=15); knee-joint SF from osteoarthritis patients: 8.6+/-8.2% (n=14); plasma from osteoarthritis patients: 5.7+/-4.8% (n=14). The results obtained by ELISA were in good agreement with those obtained by the semi-quantitative method of SDS-PAGE and Western blotting. CONCLUSIONS: We have shown that the differential heat stability of alpha1PI may be utilised as the basis for a rapid, sensitive and reproducible ELISA assay of alpha1PI inactivation. In gingival crevicular fluid from periodontal disease patients, alpha1PI is mainly inactivated and the extent of this inactivation is much higher than in inflammatory fluids from other chronic diseases such as rheumatoid arthritis. This assay could be useful in monitoring the progression of periodontal disease.