Progress on the cell therapy strategy of mesenchymal stem cells / 口腔疾病防治

@#Cell therapy based on mesenchymal stem cells (MSCs) has been a hot research topic in recent years, including the traditional cell therapy strategy based on living cells and the new cell-free therapy strategy based on soluble proteins or bioactive molecules such as extracellular vesicles (EVs). At present, MSC-induced cells have mature functions and specific structures, and insitu transplantation combined with biomaterials or organic technology has greatly improved the settlement rate and function. On the other hand, as the large-scale culture technique and EVs separation technique evolve, it is possible to obtain a large number of pure EVs, and EVs are gradually becoming a hot spot of current research. An increasing number of studies have shown that the therapeutic effect of MSCs not only occurs by implantation and differentiation but also manifests as the paracrine effect of MSCs. In this review, we discuss the emerging outcomes of cell therapies and acellular therapies to alleviate these pathological conditions.

Advances in isolation and extraction standardization and clinical translation of exosomes / 口腔疾病防治

@#Exosomes are phospholipid bilayer vesicles secreted by living cells that can carry a variety of signaling molecules, such as RNA, DNA, protein, and lipids. Exosomes play a role in the transmission of signaling molecules between cells, thus regulating many physiological and pathological processes. The methods of extracting exosomes include differential centrifugation, density gradient centrifugation, exclusion chromatography, ultrafiltration, coprecipitation, polymer immune affinity, microfluidic separation technology, etc. Each of these extraction technologies has advantages and disadvantages; however, there is no unified international standard. In addition, the expression of specific proteins and genetic material of exosomes from different cell sources are different; thus, their expression characteristics and functions are also distinctive. Based on this situation, research on exosomes is limited to preclinical studies, and difficulties and challenges still exist in clinical application. This paper summarizes the progress of research in the field of exosomes, to understand the characteristics, modification and application of exosomes from different cell sources, and to summarize their advantages and disadvantages as well as challenges, which can help researchers better understand and master the performance of exosomes. Furthermore, improvement of standard procedures in the extraction and manufacturing of exosomes is important, as it will provide a reference for researchers to carry out exosome-related translational clinical research.

CBCT study of three-dimensional morphological characteristics of upper airway in children and adolescents with skeletal class Ⅲ malocclusion / 口腔疾病防治

Objective@#To investigate the three-dimensional morphological characteristics of the upper airway in children and adolescents with skeletal class Ⅲ malformation and to explore the relationship between craniofacial structure and upper airway morphology.@*Methods @#Ninety cases of malocclusion aged 3-18 years were collected. In addition, 45 cases of type I and type Ⅲ were classified into three age groups with 15 cases in each group: 3-6 years old, 7-12 years old and 13-18 years old. CBCT was taken, and the scanning data of CBCT were reconstructed by the third-party software Invivo 5. The volume, minimum cross-sectional area, height and the ratio of sagittal diameter to transverse diameter at the minimum cross-sectional area of each segment of the upper airway were measured. The difference of the upper airway between skeletal class I and skeletal class Ⅲ in each age group was analyzed and compared by group t test.@*Results @# No significant differences in the upper airway indexes were noted between skeletal class I and skeletal class Ⅲ(P > 0.05) in the 3-6 years old group. In the 7-12 years old group, the total volume of skeletal class Ⅲ upper airway (16.25 ± 3.69 cm 3), nasopharyngeal segment (2.39 ± 0.90 cm 3), and palatopharyngeal segment (5.24 ± 1.14 cm 3) were reduced compared with the total volume of the skeletal class I upper airway (20.98 ± 6.25 cm 3) , nasopharyngeal segment (4.21 ± 1.09 cm 3), and palatopharyngeal segment (8.18 ± 2.02 cm 3), respectively, the differences were statistically significant (tVtotal=2.526, tVnose=4.999, tVpalate=4.908, P < 0.05). In the 13-18 years old group, only nasopharyngeal segment volume (3.83 ± 0.90 cm 3) was reduced in skeletal type I (4.69 ± 1.34 cm 3); the difference was statistically significant (t=2.053, P < 0.05).@*Conclusion@# Age is an important factor affecting the morphology and structure of upper airway in skeletal Ⅲ malocclusion.

A Novel Gene Mutation of Runx2 in Cleidocranial Dysplasia / 华中科技大学学报（医学）（英德文版）

Haploinsuffieiency of the runt-related transcription factor 2 (Runx2) gene is widely known to be responsible for cleidocranial dysplasia (CCD).To date,more than 190 mutations in Runx2 gene have been reported to be related to CCD.In this study,a novel mutation of Runx2 gene was observed in a female with CCD.Genomic DNA was extracted from peripheral venous blood of the proband and eleven members of her family.Genetic testing on these twelve people identified a novel missense mutation (c.895T＞C,Y299H) in exon 5 of the RUNX2 gene in the proband.This mutation results in an amino acid change at codon 895 (P.Tyr 299 His.) from a tryptophan codon (TAT) to a histidine codon (CAT).Our finding may further extend the known mutation spectrum of the RUNX2 gene,and facilitate prenatal genetic diagnosis of CCD in the future.