ABSTRACT
Induced the mouse embryonic stem(ES)cells into neural cells on silk fibroin via the improved 4-/4+ RA method to explore the effect of the silk fibroin to the ES-derived neurons' growth,adherence and differentiation.Suspended the ES cells into EBs and then transferred them to three different substrates-coated 35 mm dishes including gelatin,Bombyx mori silk fibroin(SF) and Tussah silk fibroin(TSF) to identify the adherence and proportion of ES cells-derived neurons under these three substrates.The results showed that the EBs adhered to the gelatin and TSF are faster than to the SF.The average adhesive rate on gelatin and TSF are 90.3% and 84.4% respectively,and only 38.5% on SF,all the proportion of ?-Ⅲ-Tubulin positive cells is approximately 40%.It may provide important experimental information for tissue engineering,in which ES cells-derived neuron cells and silk fibroin materials are scaffolds,and also offer a source for cell therapy research of neurodegenerative disease.
ABSTRACT
OBJECTIVE: To investigate the prevalence rate, malocclusion type and treatment rate as well as awareness of malocclusion among children and adolescents living in the Hangzhou municipality. METHODS: 1818 children and adolescents ages 7 approximate, equals 16 living in Hangzhou municipality were evaluated. RESULTS: The overall malocclusion rate was 35.75%. In Angle's classification: Angle I 593 cases (32.62%), Angle II 48 cases(2.64%),Angle III 9 cases (0.49%). Among the malocclusion type of crowding was mixed dentition 70.66%,permanent dentition 85.89%. In the overjet malocclusion mixed dentition was noted in 60.57% and permanent dentition in 51.05%.The type of overbite was mixed dentition 67.82%,permanent dentition 31.23%. In the crossbite of anterior teeth mixed dention was noted in 12.30% and permanent dention in 9.91%. Overall treatment rate for malocclusion was 10.15%.CONCLUSION: Among Hangzhou municipality juveniles there is both inadequate prevention and treatment of dental malocclusion.