破骨细胞异质性的研究进展

破骨细胞是参与骨改建过程的关键细胞。近年来,越来越多的证据表明人体不同部位的破骨细胞生物学特性存在着差异,即破骨细胞异质性。但破骨细胞异质性的产生机制尚不明确,不同部位参与诱导破骨细胞形成的成骨细胞存在差异;不同部位破骨细胞所黏附的骨基质结构及组成成分不同;不同部位破骨前体细胞不同,可能是其产生的机制。     

破骨细胞整合素的功能

整合素是一类重要的细胞表面跨膜蛋白，介导细胞粘附，并参与细胞内外的信号传递。近年来研究发现，它在破骨细胞迁移、分化、粘附、信号传导等过程中起重要作用，本文对其研究现状作一综述。     

破骨细胞整合素的功能

整合素是一类重要的细胞表面跨膜蛋白,介导细胞粘附,并参与细胞内外的信号传递。近年来研究发现,它在破骨细胞迁移、分化、粘附、信号传导等过程中起到重要作用,本文对其研究现状作一综述。     

破骨细胞的来源

有关破骨细胞的来源学术界一直存在争议，本文结合近年来有关破骨细胞分化诱导因子的一些研究，着重就其与单核－巨噬系统细胞的关系作了回顾。在导致破骨细胞的分化过程中，前体细胞RANK信号传导通路的激活至关重要。对RANK及可能存在的其它信号传导通路的研究可能会有助于理解破骨细胞的来源及其与单核－巨噬系统细胞的关系。     

破骨细胞形成和骨吸收机理

破骨细胞形成和骨吸收机理赵守亮综述史俊南肖明振审阅西安第四军医大学口腔医学院（７１００３２）破骨细胞是具有破坏骨组织和其它矿化物能力的一群多核细胞，它不仅在病理条件下，而且在生理条件下也起着重要的作用，如：骨组织的发育、功能性改建等，都是在破骨细胞与...     

破骨细胞与颌骨骨吸收研究展望

颌骨在全身骨组织中占有重要而特殊的地位，其包绕牙齿的部分——牙槽骨，由于与牙齿的密切关系，是全身骨代谢最活跃的部分。多种疾患，如颌骨的炎症、囊肿、肿瘤、骨质疏松症等均可引起颌骨与牙槽骨骨质吸收亢进，致使牙齿松动、脱落，影响咀嚼功能，甚至引起颌骨局部缺损，影响颌面部     

破骨细胞的来源

有关破骨细胞的来源学术界一直存在争议,本文结合近年来有关破骨细胞分化诱导因子的一些研究,着重就其与单核—巨噬系统细胞的关系作了回顾。在导致破骨细胞的分化过程中,前体细胞RANK信号传导通路的激活至关重要。对RANK及可能存在的其它信号传导通路的研究可能会有助于理解破骨细胞的来源及其与单核—巨噬系统细胞的关系。     

补骨脂对分离破骨细胞作用研究

本研究从日本大耳白兔的四肢长骨中分离出破骨细胞，与牛骨片在体外共同培养。在培养液中添加不同浓度补骨脂并设立对照，用倒置相差显微镜观察。结果表明：较高浓度补骨脂（１０－４ｍｏｌ／Ｌ）能抑制分离的破骨细胞在骨片上形成的吸收陷窝的增加与扩张（Ｐ＜０．０５）。低浓度（５Ｘ１０一５ｍｏｌ／Ｌ）对破骨细胞作用不显著（Ｐ＞０．５）。     

破骨细胞促进骨重建的研究进展

骨重建在口腔医学领域具有重要的价值,而破骨细胞对于骨重建具有不可替代的促进作用。目前,以破骨细胞-成骨细胞耦联为靶向,即利用破骨细胞促进骨重建的研究和应用极少。本文就骨吸收和骨生成间的动态耦联、破骨细胞对骨重建的促进作用、破骨细胞促进骨重建的分子机制等研究进展作一综述。     

牙囊前体细胞的研究进展

牙囊前体细胞(DFPC)是一类具有自我更新和多向分化潜能的牙源性干细胞.DFPC属于间充质干细胞,可被诱导分化为成纤维样、成骨、成牙骨质样、脂肪样和神经样细胞.本文就DFPC的培养、鉴定和定向分化,DFPC与脱落乳牙干细胞间的比较等研究进展作一综述.     

流体剪切力作用强度对极化破骨细胞ATP6V1a1 mRNA的影响

目的观察不同作用强度流体剪切力对鼠极化破骨细胞ATP6V1a1 mRNA表达水平的影响。方法联合应用形态学观察、特异性染色和吸收实验,对长骨机械分离法获得的正在进行骨吸收的极化破骨细胞进行培养鉴定。然后将细胞分为对照组和0.9、2.9、8.7、26.3 dynes/cm2实验组,作用时间30 min,行实时荧光定量PCR检测ATP6V1a1 mRNA表达水平,并进行统计分析。结果获得的细胞满足破骨细胞的鉴定标准,属于正在进行骨吸收的极化破骨细胞。对照组和0.9、2.9、8.7、26.3 dynes/cm2实验组ATP6V1a1 mRNA表达量分别为（1.14±0.06）×106、（1.62±0.09）×106、（2.28±0.13）×106、（3.24±0.18）×106、（9.16±0.53）×106 个拷贝数,所有组间均有显著性差异（P<0.05）。结论极化破骨细胞对流体剪切力反应敏感,随着加载强度的增加,ATP6V1a1 mRNA表达水平有增加趋势。     

体外培养鼠破骨细胞对牙体硬组织的吸收实验

目的本文旨在观察体外培养鼠破骨细胞对牙体硬组织的吸收。方法采用鼠长骨机械分离法获得破骨细胞,通过破骨细胞形态学观察及其特异性染色鉴定后,在牙本质上培养破骨细胞并用扫描电镜观察其吸收情况。结果鼠破骨细胞能在牙本质磨片上形成大小不一、形态不规则的吸收陷窝。结论长骨机械分离法可获得一定量特异性染色阳性的破骨细胞,并可在牙本质磨片上形成明显吸收陷窝。     

Effects of T cell adoptive transfer into nude mice on alveolar bone resorption induced by endotoxin

Using the method of reconstitution of nude mice with T cells, we examined the effects of T cell on alveolar bone resorption induced by repeated injections of Escherichia coli endotoxin into periodontal tissue. Three mice groups (normal, nude and T cell reconstituted nude mice) were used. Endotoxin derived from E. coli was repeatedly injected into the gingiva of the mice left mandibles every 48 h and the mice were killed on the day after the 1st, 4th, 7th, 10th, 13th and 20th injections of endotoxin. Alveolar bone resorption was examined histopathologically and histomorphometrically. Bone surfaces in contact with the osteoclast were defined as the site of active resorption and the ratios of active resorption were compared among the 3 nice groups. Consequently, no active resorption was found after the first injection of endotoxin in any group. After the 4th injection, active resorption was found in normal nice and T cell reconstituted nude mice and gradually rose with the increase in the injection frequency. In contrast, few osteoclasts were found even after the 10th injection in the nude mice. In addition, there were statistically significant differences between the normal price and nude mice after the 4th and 10th injections (p<0.05). These findings suggested that T cell influences periodontal bone destruction induced by local administration of endotoxin during the early phases.     

Reduced growth hormone receptor immunoreactivity in osteoclasts adjacent to the erupting molar in the incisor-absent (osteopetrotic) rat

First molars fail to erupt in the incisor-absent (ia/ia) rat because of a defect in osteoclast function. Growth factors that regulate local bone metabolism include growth hormone (GH), insulin-like growth factor-I (IGF-I), epidermal growth factor (EGF) and interleukin-1 alpha (IL-1alpha). Since osteoclast function may be affected by these factors, the aim of this study was to determine the distribution of GH receptor (GHr), IGF-I, EGF and IL-1alpha, in osteoclasts located occlusal to the erupting first molar, in the 'eruption pathway', in normal and ia/ia rats. Sagittal sections of the first molar and adjacent bone from 3- and 9-d-old animals were examined. Osteoclasts were identified using tartrate-resistant acid phosphatase (TRAP). The TRAP-positive osteoclast cell numbers were higher in ia/ia animals at 3 and 9 days-of-age. In the ia/ia group, fewer osteoclasts were GHr- and IGF-I-positive at 3 d of age, and at 9 d of age fewer osteoclasts were GHr-positive. In the ia/ia rat, defective osteoclast function failed to resorb bone to provide an eruption pathway for the lower first molar. The expression of GHr, and to some degree IGF-I, by these osteoclasts was reduced, which may be related to their ability to differentiate and function.     

正畸牙移动中骨吸收机制及其调控的研究进展

破骨细胞在正畸牙移动压力侧骨吸收过程中发挥着重要的作用,针对破骨细胞分化成熟及其发挥功能的调控研究,能为正畸治疗中控制牙齿移动提供新的思路,同时有助于防治正畸治疗中出现的牙根外吸收等。     

Decrease in the number and apoptosis of alveolar bone osteoclasts in estrogen-treated rats

BACKGROUND AND OBJECTIVE: Bone is a mineralized tissue that is under the influence of several systemic, local and environmental factors. Among systemic factors, estrogen is a hormone well known for its inhibitory function on bone resorption. As alveolar bone of young rats undergoes continuous and intense remodeling to accommodate the growing and erupting tooth, it is a suitable in vivo model for using to study the possible action of estrogen on bone. Thus, in an attempt to investigate the possibility that estrogen may induce the death of osteoclasts, we examined the alveolar bone of estrogen-treated rats. MATERIAL AND METHODS: Fifteen, 22-d-old female rats were divided into estrogen, sham and control groups. The estrogen group received estrogen and the sham group received corn oil used as the dilution vehicle. After 8 d, fragments containing alveolar bone were removed and processed for light microscopy and transmission electron microscopy. Sections were stained with hematoxylin and eosin and tartrate-resistant acid phosphatase (TRAP)-an osteoclast marker. Quantitative analysis of the number of TRAP-positive osteoclasts per mm of bone surface was carried out. For detecting apoptosis, sections were analyzed by the Terminal deoxynucleotidyl transferase-mediated dUTP Nick-End Labeling (TUNEL) method; TUNEL/TRAP combined methods were also used. RESULTS: The number of TRAP-positive osteoclasts per mm of bone surface was significantly reduced in the estrogen group compared with the sham and control groups. TRAP-positive osteoclasts exhibiting TUNEL-positive nuclei were observed only in the estrogen group. In addition, in the estrogen group the ultrastructural images revealed shrunken osteoclasts exhibiting nuclei with conspicuous and tortuous masses of condensed chromatin, typical of apoptosis. CONCLUSION: Our results reinforce the idea that estrogen inhibits bone resorption by promoting a reduction in the number of osteoclasts, thus indicating that this reduction may be, at least in part, a consequence of osteoclast apoptosis.     

组织工程骨干细胞的研究进展

随着再生医学的迅速发展,组织工程骨为骨缺损的修复提供了一个新方法,因而成为研究的热点,而干细胞作为组织工程成骨过程中非常重要的环节,同样受到了极大的关注。干细胞的特点是具有能够在特定条件下分化为不同类型细胞的能力。本文就能够分化为成骨细胞的干细胞的分类及各自特点的相关研究进行综述。     

Inhibitory effect of a bisphosphonate (risedronate) on experimental periodontities in rats

The present study was designed to examine whether systemic administration of a bisphosphonate, risedronate, could prevent alveolar bone resorption in rats with experimental periodontitis. On Day 1, an elastic ring was placed around the neck of the right mandibular 1st molar to induce inflammatory periodontitis. The animals were given daily injections of either 0.9% NaCl (control group), or 0.8, 1.6 or 3.2 Öoles/kg (s.c.) of risedronate (experimental groups) from Days 1 to 7, and were killed on Day 8. Histological examinations and determination of bone mineral density in the interdental area between the 1st and 2nd molars with an image analyzer revealed that the presence of the elastic ring induced a loss of attachment and bone resorption in the control group. Vigorous bone resorption, with appearance of a large number of osteoclasts, was observed in the interdental and bifurcation areas. In the experimental groups, however, the resorption of alveolar bone and the loss of bone mineral content in these areas were prevented in a dose-dependent fashion, especially at doses of 1.6 and 3.2 Ömoles/kg. Many osteoclasts were detached from the surface of the alveolar bone and had degenerated appearances, such as rounded shapes, loss of polarity and pyknosis. These results suggest that administration of risedronate is effective in preventing bone resorption in periodontitis.