Diego Moura Soares

Effect of a cryopreservation protocol on the proliferation of stem cells from human exfoliated deciduous teeth

Abstract Objective: The aim of the present study was to evaluate the influence of a cryopreservation protocol on the proliferation and viability of stem cells from human exfoliated deciduous teeth (SHEDs). Materials and methods: Cells from the pulp of three deciduous teeth were isolated and characterized to confirm their stem cell nature. In second passage, part of the cells were submitted to normal conditions of cell culture (Control group), while part of the cells were maintained in 10% DMSO diluted in foetal bovine serum and submitted to the following cryopreservation protocol: 2 h at 4 °C, 18 h at −20 °C and then at −80 °C for two intervals (30 days – Cryopreservation I; and 180 days Cryopreservation II). Cell proliferation and cell cycle were evaluated at intervals of 24, 48 and 72 h after plating, and apoptosis-related events were analyzed at 72 h. Results: All groups exhibited an increase in the number of cells, and no significant differences between the cryopreserved and control groups were observed (p > .05). The distribution of cells in the cell cycle phases was consistent with cell proliferation, and the percentage of viable cells was higher than 99% in all groups, indicating that cell viability was not affected by the cryopreservation protocol throughout the experiment. Conclusion: The proposed cryopreservation protocol is adequate for the storage of SHED, permitting their use in future experimental studies.

Influência de um protocolo de criopreservação no rendimento in vitro de células-tronco derivadas do tecido adiposo

Background: Adipose tissue obtained by liposuction may be an accessible source of stem cells for future clinical application in tissue regeneration. Cryopreservation maintains stem cells in a live state for long periods of time, without impairing their function. The aim of this study was to assess the effect of a cryopreservation protocol on the proliferation of adipose-derived stem cells. Methods: Fragments of mouse adipose tissue were subjected to enzymatic digestion in order to isolate cells that were then cultured in minimum essential medium (α-MEM) supplemented with 10% fetal bovine serum (FBS). Cells were main tained at 37°C in 5% carbon dioxide (CO 2 ). At the first passage, an aliquot of 1 × 10 6 cells was cryopreserved in FBS with 10% dimethylsulfoxide (DMSO) for 30 days, whereas the remaining cells were seeded and maintained in culture. When these cells reached the third passage, the 2 groups of cells (cryopreserved and non-cryopreserved) were seeded for experiments. Cell viability and proliferation curves were established at intervals of 24, 48, and 72 hours by counting cells with a hemocytometer and MTT assay. Nuclear morphology was assessed by DAPI staining. The data were statistically analyzed, with a significance level of 5%. Results: Increasing cellular proliferation was observed in both groups, with no significant difference throughout the experiment (P > 0.05). There was no significant change in cell viability and signs of nuclear damage were not detected in both the groups studied. Conclusions: The cryopreservation protocol analyzed was effective for maintaining the integrity of adipose-derived stem cells, allowing their storage for later use.

Aesthetic evaluation and therapeutic procedures related to main facial profiles

Introduction: Orthognathic surgery for correction of dentofacial deformities provides a more-symmetrical face, and functional and aesthetic benefits. The aim of this study was to evaluate the perception of buccomaxillofacial surgeons regarding the aesthetics of facial profiles patterns I, II, and III in related to sex, ethnicity, and the main therapeutic procedures. Methods: We interviewed 18 specialist surgeons or surgeons in training in buccomaxillofacial surgery by using a standardized clinical report form for aesthetic evaluation and therapeutic procedures of 12 manipulated images simulating facial profiles, sex, and race. Results: As for aesthetics, the highlights were that facial profile type I had the highest mean values, whereas facial profile type III had the lowest mean values. However, no significant differences were found between the mean values obtained in different facial profiles in relation to sex and race. The therapeutic procedures were homogeneous in profiles II and III, with higher percentages for classical procedures in the orthosurgical treatment of these dentofacial deformities. Conclusion: Facial profile I was considered more aesthetic. Furthermore, sex and racial type effects on aesthetics for the studied sample. Facial profiles I were the most difficult to assess as to therapeutic procedures, which resulted in a wide range of options in relation to profiles II and III.

RENDIMENTO DE CÉLULAS MESENQUIMAIS DO TECIDO ADIPOSO SUBMETIDAS A DIFERENTES PROTOCOLOS DE EXTRAÇÃO

Objetivo: Estabelecer um protocolo de extracao de celulas mesenquimais do tecido adiposo, a partir da avaliacao do rendimento celular em dois metodos de digestao enzimatica do tecido. Material e Metodos: Fragmentos de tecido adiposo foram extraidos da regiao inguinal de camundongos e processados por dois protocolos distintos: Grupo 1 – digestao enzimatica com colagenase I; Grupo 2 – digestao enzimatica com colagenase I e tripsina/EDTA, ambos por 1 hora a 37°C. No terceiro subcultivo (P3) as celulas dos dois grupos foram submetidas a contagem em Câmara de Neubauer para avaliacao da proliferacao celular e obtencao da curva de crescimento nos intervalos de 24, 48 e 72 horas. Foi realizada a marcacao pelo DAPI no intervalo de 72 horas, nos grupos estudados, para avaliar a existencia de danos morfologicos nucleares. Os dados foram analisados estatisticamente, com nivel de significância de 5%. Resultados: Os dois grupos exibiram um padrao de crescimento celular ascendente. As medias das contagens celulares demonstraram uma maior proliferacao celular no grupo I, com diferenca estatisticamente significante entre os grupos nos intervalos de 48 e 72 horas (p<0,05). Alteracoes morfologicas nucleares nao foram observadas nos grupos. Conclusao: A digestao enzimatica do tecido adiposo por colagenase I, sem associacao com a tripsina, proporcionou melhor rendimento das celulas mesenquimais, o que favorece a escolha desse protocolo em experimentos com este tipo celular. DESCRITORES: Tecido Adiposo. Tecnicas de Cultura de Celulas. Proliferacao Celular.

Lateral periodontal cyst with extremely rare clinical-radiographic presentation

PURPOSE: The present article describes the clinical, radiographic and histological features of an extremely rare case of lateral periodontal cyst as well as the treatment and postoperative follow-up. CASE DESCRIPTION: A 43-year-old male patient, mulatto, sought the Stomatology Clinic of the Caruaru Dental School (Brazil) with a complaint of increased volume on the right side of his face for approximately five years. The increase in volume was asymptomatic and facial asymmetry was the main reason he sought treatment. Based on the clinical and imaging exams as well as the lack of pulp vitality in tooth 13, the presumed clinical diagnosis was inflammatory radicular cyst and the surgical plan was total cystic enucleation. Excisional biopsy was performed and sent for pathologic microscopic analysis, which revealed multiple cavities with hyalinization of the connective tissue below the epithelium and the presence of clear non-epithelial cells. CONCLUSION: The case reported reveals that the extremely rare botryoid variant of lateral periodontal cyst exhibits multilocular presentation and excessive growth. Excisional biopsy was the treatment for this case and no sign of recurrence was observed over the nine-month follow-up period.