A Iarge number of enantiornithine birds are discovered from the Early Cretaceous Jiufutang Formation in western Liaoning, China. They are all small-sized birds with a few small teeth. The enantiornithine bird from the...A Iarge number of enantiornithine birds are discovered from the Early Cretaceous Jiufutang Formation in western Liaoning, China. They are all small-sized birds with a few small teeth. The enantiornithine bird from the Jiufutang Formation in the Shangheshou area, Chaoyang, Liaoning Province reported in this paper is the largest individual known in all enantiornithine birds of the Early Cretaceous. However, its teeth possess a feature of pseudoheterodont. Some different development stages of the new teeth substitute the earlier stages and the stages of development are preserved in this specimen. This development pattern is similar to that of Archaeopteryx and alligator but not dinosaur. A well-developed postorbital was also preserved in the skull, which was a diapsidian skull like that of Confuciusornis. Additionally, the distinctive preservation of its prefrontal distinguishes it from other enantiornithine birds of the Early Cretaceous.展开更多
背景:目前对于骨性Ⅲ类错(牙合)的诊断和治疗都具有一定的挑战性,主要是因为这类错(牙合)类型的患者颅面部结构生长的多样性和不可预测性,治疗决策及其成败在很大程度上取决于骨性Ⅲ类错(牙合)患者未来的生长潜力。目的:综述儿童骨性Ⅲ...背景:目前对于骨性Ⅲ类错(牙合)的诊断和治疗都具有一定的挑战性,主要是因为这类错(牙合)类型的患者颅面部结构生长的多样性和不可预测性,治疗决策及其成败在很大程度上取决于骨性Ⅲ类错(牙合)患者未来的生长潜力。目的:综述儿童骨性Ⅲ类错(牙合)牙弓和基骨弓生长发育的研究现状研究进展。方法:在PubMed、中国知网、万方、Medline数据库中进行相关文献检索,以“malocclusion,skeletal class Ⅲ malocclusion,dental arch,basal arch,growth and development,mixed dentition,tongue,etiology,jaw”为英文检索词进行检索,以“错(牙合)、骨性Ⅲ类错(牙合)、牙弓、基骨弓、生长发育、替牙期、舌、病因、颌骨”为中文检索词进行检索,最后纳入64篇文献进行仔细阅读分析与总结。结果与结论:①骨性Ⅲ类错(牙合)畸形是儿童(牙合)发育异常中较为常见的一种错(牙合)类型,其颌骨、牙弓、基骨弓在一定程度上也会受到遗传和环境因素的影响。②颌骨、牙弓、基骨弓作为特殊的颅颌面复合体有相同的增长变化趋势,具有协同性。③骨性Ⅲ类错(牙合)患儿的上、下颌骨生长速率与年龄和骨龄相关,颌骨长度的增长在不同生长高峰期的速率也有差异,一直持续到患儿成年。④正确预测生长发育高峰期,抑制骨性Ⅲ类儿童下颌骨的生长发育就显得尤为重要。⑤由于骨性Ⅲ类错(牙合)畸形的治疗具有复杂性,因此及时发现上、下颌骨、牙齿、牙列及咬合关系等异常发育的情况,正确诊断,早期矫治,适时干预对于引导儿童颅颌面的正常生长发育具有重要意义。⑥目前对于儿童牙弓、基骨弓生长发育的研究主要集中在正常(牙合),因为骨性Ⅲ类错(牙合)畸形患儿一旦开始治疗,就不能继续观察其生长发育特点,因此未来还需对骨性Ⅲ类错(牙合)畸形的生长发育机制进行进一步研究。展开更多
The spatiotemporal relationships in high-resolution during odontogenesis remain poorly understood.We report a cell lineage and atlas of developing mouse teeth.We performed a large-scale(92,688 cells)single cell RNA se...The spatiotemporal relationships in high-resolution during odontogenesis remain poorly understood.We report a cell lineage and atlas of developing mouse teeth.We performed a large-scale(92,688 cells)single cell RNA sequencing,tracing the cell trajectories during odontogenesis from embryonic days 10.5 to 16.5.Combined with an assay for transposase-accessible chromatin with high-throughput sequencing,our results suggest that mesenchymal cells show the specific transcriptome profiles to distinguish the tooth types.Subsequently,we identified key gene regulatory networks in teeth and bone formation and uncovered spatiotemporal patterns of odontogenic mesenchymal cells.CD24^(+)and Plac8^(+)cells from the mesenchyme at the bell stage were distributed in the upper half and preodontoblast layer of the dental papilla,respectively,which could individually induce nonodontogenic epithelia to form tooth-like structures.Specifically,the Plac8^(+)tissue we discovered is the smallest piece with the most homogenous cells that could induce tooth regeneration to date.Our work reveals previously unknown heterogeneity and spatiotemporal patterns of tooth germs that may lead to tooth regeneration for regenerative dentistry.展开更多
基金the Grand Project of the National Natural Science Foundation of China(Grant No.4983002)the National Natural Science Foundation of China(Grant No.49920026,40072006)+1 种基金Specialized Research Fund for the Doctoral Program of Higher Education(Grant No.20020145002) the keytask project of Science and Technology of Liaoning Province(Grant No.2001230001).
文摘A Iarge number of enantiornithine birds are discovered from the Early Cretaceous Jiufutang Formation in western Liaoning, China. They are all small-sized birds with a few small teeth. The enantiornithine bird from the Jiufutang Formation in the Shangheshou area, Chaoyang, Liaoning Province reported in this paper is the largest individual known in all enantiornithine birds of the Early Cretaceous. However, its teeth possess a feature of pseudoheterodont. Some different development stages of the new teeth substitute the earlier stages and the stages of development are preserved in this specimen. This development pattern is similar to that of Archaeopteryx and alligator but not dinosaur. A well-developed postorbital was also preserved in the skull, which was a diapsidian skull like that of Confuciusornis. Additionally, the distinctive preservation of its prefrontal distinguishes it from other enantiornithine birds of the Early Cretaceous.
文摘背景:目前对于骨性Ⅲ类错(牙合)的诊断和治疗都具有一定的挑战性,主要是因为这类错(牙合)类型的患者颅面部结构生长的多样性和不可预测性,治疗决策及其成败在很大程度上取决于骨性Ⅲ类错(牙合)患者未来的生长潜力。目的:综述儿童骨性Ⅲ类错(牙合)牙弓和基骨弓生长发育的研究现状研究进展。方法:在PubMed、中国知网、万方、Medline数据库中进行相关文献检索,以“malocclusion,skeletal class Ⅲ malocclusion,dental arch,basal arch,growth and development,mixed dentition,tongue,etiology,jaw”为英文检索词进行检索,以“错(牙合)、骨性Ⅲ类错(牙合)、牙弓、基骨弓、生长发育、替牙期、舌、病因、颌骨”为中文检索词进行检索,最后纳入64篇文献进行仔细阅读分析与总结。结果与结论:①骨性Ⅲ类错(牙合)畸形是儿童(牙合)发育异常中较为常见的一种错(牙合)类型,其颌骨、牙弓、基骨弓在一定程度上也会受到遗传和环境因素的影响。②颌骨、牙弓、基骨弓作为特殊的颅颌面复合体有相同的增长变化趋势,具有协同性。③骨性Ⅲ类错(牙合)患儿的上、下颌骨生长速率与年龄和骨龄相关,颌骨长度的增长在不同生长高峰期的速率也有差异,一直持续到患儿成年。④正确预测生长发育高峰期,抑制骨性Ⅲ类儿童下颌骨的生长发育就显得尤为重要。⑤由于骨性Ⅲ类错(牙合)畸形的治疗具有复杂性,因此及时发现上、下颌骨、牙齿、牙列及咬合关系等异常发育的情况,正确诊断,早期矫治,适时干预对于引导儿童颅颌面的正常生长发育具有重要意义。⑥目前对于儿童牙弓、基骨弓生长发育的研究主要集中在正常(牙合),因为骨性Ⅲ类错(牙合)畸形患儿一旦开始治疗,就不能继续观察其生长发育特点,因此未来还需对骨性Ⅲ类错(牙合)畸形的生长发育机制进行进一步研究。
基金supported by the National Key Research and Development Program of China Stem Cell and Translational Research,China(2017YFA0104800)the Research Funds from Health@InnoHK Program launched by Innovation Technology Commission of the Hong Kong SAR,China+4 种基金National Natural Science Foundation of China(81570944 and 92068201)Science and Technology Planning Project of Guangdong Province,China(2020B1212060052)High-level Hospital Construction Project(DFJHBF202110)Youth Innovation Promotion of the Chinese Academy of Sciences(2019348)Guangzhou Key Medical Disciplines(2021–2023)。
文摘The spatiotemporal relationships in high-resolution during odontogenesis remain poorly understood.We report a cell lineage and atlas of developing mouse teeth.We performed a large-scale(92,688 cells)single cell RNA sequencing,tracing the cell trajectories during odontogenesis from embryonic days 10.5 to 16.5.Combined with an assay for transposase-accessible chromatin with high-throughput sequencing,our results suggest that mesenchymal cells show the specific transcriptome profiles to distinguish the tooth types.Subsequently,we identified key gene regulatory networks in teeth and bone formation and uncovered spatiotemporal patterns of odontogenic mesenchymal cells.CD24^(+)and Plac8^(+)cells from the mesenchyme at the bell stage were distributed in the upper half and preodontoblast layer of the dental papilla,respectively,which could individually induce nonodontogenic epithelia to form tooth-like structures.Specifically,the Plac8^(+)tissue we discovered is the smallest piece with the most homogenous cells that could induce tooth regeneration to date.Our work reveals previously unknown heterogeneity and spatiotemporal patterns of tooth germs that may lead to tooth regeneration for regenerative dentistry.
