RESUMO
Type 1 diabetes mellitus (T1DM), associated with autoimmune destruction of pancreatic ß cells, is observed in children and adolescents. OBJECTIVE: We investigated the potential association of the apolipoprotein M (APOM) polymorphisms rs707921, rs805264, rs805296, rs805297, and rs9404941 in childhood-onset T1DM (n = 144) and compared them to those in healthy (mostly Euro-Brazilian) children (n = 168). METHODS: This project was approved by the Ethics Committee of the Federal University of Parana (CAAE 24676613.6.0000.0102). Genotyping was performed using PCR-restriction fragment length polymorphisms (rs805296 and rs9404941) and TaqMan probes (rs707921, rs805264, and rs805297). RESULTS: All polymorphisms were in Hardy-Weinberg equilibrium. In the codominant model, no significant differences (P > 0.05) were observed in genotype and allele frequencies between healthy controls and children with T1DM. The minor allele frequencies (95% CI) for healthy subjects were rs707921 (A, 10.7%; 7-14%), rs805264 (A, 6.5%; 4-9%), rs805296 (C, 3.6%; 2-6%), rs805297 (A, 22.6%; 22-31%), and rs9404941 (C, 2.7%; 1-4%). The frequencies of the rs805297 A allele and rs805296 C allele were similar to those of other Caucasian populations; both the rs707921 and rs805264 A alleles were similar to American and Latin American populations, whereas that of the rs9404941 C allele was lower than that observed in the Caucasian and Asian populations. CONCLUSIONS: Haplotype analysis suggests that rs805297-C, rs9404941-T, rs805296-T, rs805264-G, and rs707921-C conferred risk (OR: 4.25; 95% CI: 1.81-10.1) to childhood-onset T1DM in the Euro-Brazilian population.
RESUMO
Contraction due to polymerization of dental resin can cause failure on the adhesive interfaces, can lead to problems such as the appearance of gaps in the interfaces, postoperative sensitivity, pulp damage and the return of the caries. The objective of this work is the study of stresses on the dental adhesive that are generated by the process shrinkage of resin associated with biting forces. A laboratory experiment measured the strains and temperature inside the FiltekTM Bulk Fill Flow resin during the process of polymerization using Fiber Bragg Grating sensors in an ex vivo tooth. From tomographic images a three-dimensional geometric model of the tooth was reconstructed. A pre-tension was calibrated to simulate the residual contraction on the resin 3 D model. Finally, an Finite Element Method analysis was performed to access the adhesive stresses at the interface enamel/dentin with the adhesive, considering as loading the residual polymerization contraction of the dental resin and also biting loads. The model was able to represented the strain obtained in the laboratory experiment. The results of the stress analysis shows that the outer regions of adhesive are more prone to failure, as veried by dental surgeons in clinical practice.