RESUMO
BACKGROUND: Bone tissue is one of the tissues that are capable of self-regeneration. However, bone self-regeneration is defeated in the case of broad lesion of bone structure. Isolated stem cells from wisdom tooth follicles can potentially differentiate into ectodermal and mesodermal cells. Saghez is a natural substance that has been extracted from Pistacia terebinthus with unique features, such as high temperature and mechanical stability, adhesive structure, biocompatibility, and anti-neoplastic properties. METHODS: In this study, Saghez-encapsulated BMP2 was applied as a scaffold for wisdom tooth follicle stem cell differentiation into the osteocyte. A total of three wisdom tooth follicles were obtained for stem cell isolation. For verification of differentiation of the isolated stem cells into osteocyte and adipocyte, Oil Red and Alizarin staining were applied, respectively. Moreover, mesenchymal stem cells were distinguished by profiling their cell surface markers, includingCD73, CD90, CD44, and CD105, by flow cytometry. Saghez scaffold loaded with BMP2 factor was prepared using sol-gel method. Four experimental groups were considered in this study: cells seeded on BMP2 encapsulated in Saghez scaffold, Saghez scaffold, osteogenic medium, and DMEM medium. RESULTS: Mechanical properties of Saghez scaffold, including tensile Young's modulus, ultimate tensile stress, compression Young's modulus, and complex shear modulus, were 19 MPa, 32 MPa, 0.42 MPa, and 0.9 MPa, respectively. The porosity of the scaffold was 70-140 µm, and the percentage of porosity was 75-98%. The results of flow cytometry studies indicated that CD44, CD73, CD90, and CD105 were positively expressed on the membrane of the tooth follicles' stem cell. The results indicated that the rate of differentiation of the follicle stem cells into osteocyte was the highest in the Saghez-BMP2 scaffold containing differentiation medium groups. These findings were verified by morphological studies, osteoblast and osteocalcin gene and protein expression investigations, and alkaline phosphatase activity measurement. The highest osteopontin and osteocalcin genes expression levels (1.7 and 1.9) were seen in positive control, followed by DMEM + differentiation factor (1.5 and 1.6), scaffold + BMP2 (1.2 and 1.4), DMEM + stem cell (1 and 1) and scaffold (0.4 and 0.5), and negative control respectively. CONCLUSION: This study provides a novel system for differentiation of the stem cell into osteocytes. The results of this study suggest that loaded BMP2 in Saghez scaffold possibly acts as an osteocyte differentiator factor.
Assuntos
Proteína Morfogenética Óssea 2/farmacologia , Saco Dentário/citologia , Osteócitos/citologia , Células-Tronco/citologia , Alicerces Teciduais/química , Fenômenos Biomecânicos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultura , Saco Dentário/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Dente Serotino/citologia , Osteócitos/efeitos dos fármacos , Osteogênese , Porosidade , Células-Tronco/efeitos dos fármacosRESUMO
For cervical cancer cases with a low risk of relapse who wish to maintain their fertility, radical trachelectomy is an alternative to radical hysterectomy. Pelvic magnetic resonance imaging is recommended before surgery, with laparoscopic assisted lymphatic dissection required for assessment of lymphatic metastasis. If there is a visible lesion in the cervix, the specimen taken during trachelectomy should be sent for frozen section. The complications of radical trachelectomy are chronic vaginal discharge, irregular vaginal bleeding, dysmenorrhea, ulceration, amenorrhea and cervical stenosis. The probability of cervical cancer recurrence with a lesion of similar size is comparable with radical trechelectomy and radical hysterectomy. Two thirds of pregnancies after trachelectomy lead to live births of which approximately 40% of them are healthy. However, the probability of second trimester abortion and pre-term labor is greater than in the general population. Because of the possibility of uterine arterial injury in short cervix, vaginal delivery should be avoided and a cesarean operation in 37-38th week is recommended. Adjuvant treatment with chemotherapy followed by radical trachelectomy is a suitable option for larger lesions. On the other hand, conization or simple trachelectomy are more proper approaches for very small lesions.