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81.
Morinha F Albuquerque C Requicha J Dias I Leitão J Gut I Guedes-Pinto H Viegas C Bastos E 《Gene》2011,485(2):139-145
Periodontal disease (PD) is the most common inflammatory disease of the oral cavity of domestic carnivores. In Human Medicine molecular genetics research showed that several genes play a role in the predisposition and progression of this complex disease, primarily through the regulation of inflammatory mediators, but the exactly mechanisms are poorly understood. This study aims to contribute to the characterization of the genetic basis of PD in the dog, a classically accepted model in Periodontology. We searched for genetic variations in the interleukin-6 (IL6) gene, in order to verify its association with PD in a case-control study including 25 dogs in the PD case group and 45 dogs in the control group. We indentified and characterized three new genetic variations in IL6 gene. No statistically significant differences were detected between the control and PD cases groups. Our results do not support an evidence for a major role contribution of these variants in the susceptibility to PD in the analyzed population. Nevertheless, the sequence variant I/5_g.105 G > A leads to an amino acid change (arginine to glutamine) and was predicted to be possibly damaging to the IL6 protein. A larger cohort and functional studies would be of extreme importance in a near future to understand the possible role of IL6 variants in this disease. 相似文献
82.
Yokoi T Saito M Kiyono T Iseki S Kosaka K Nishida E Tsubakimoto T Harada H Eto K Noguchi T Teranaka T 《Cell and tissue research》2007,327(2):301-311
The dental follicle is a mesenchymal tissue that surrounds the developing tooth germ. During tooth root formation, periodontal
components, viz., cementum, periodontal ligament (PDL), and alveolar bone, are created by dental follicle progenitors. Here,
we report the presence of PDL progenitors in mouse dental follicle (MDF) cells. MDF cells were obtained from mouse incisor
tooth germs and immortalized by the expression of a mutant human papilloma virus type 16 E6 gene lacking the PDZ-domain-binding motif. MDF cells expressing the mutant E6 gene (MDF
E6-EGFP
cells) had an extended life span, beyond 150 population doublings (PD). In contrast, normal MDF cells failed to proliferate
beyond 10 PD. MDF
E6-EGFP
cells expressed tendon/ligament phenotype-related genes such as Scleraxis (Scx), growth and differentiation factor-5, EphA4, Six-1, and type I collagen. In addition, the expression of periostin was observed. To elucidate the differentiation capacity of MDF
E6-EGFP
cells in vivo, the cells were transplanted into severe combined immunodeficiency mice. At 4 weeks, MDF
E6-EGFP
cell transplants had the capacity to generate a PDL-like tissue that expressed periostin, Scx, and type XII collagen and the fibrillar assembly of type I collagen. Our findings suggest that MDF
E6-EGFP
cells can act as PDL progenitors, and that these cells may be a useful research tool for studying PDL formation and for developing
regeneration therapies.
This work was supported by a Grant-in Aid for the High-Tech Research Center Project from the Ministry of Education, Culture,
Sports, Science, and Technology of Japan, the AGU High-Tech Research Center Project, the 2003-Multidisciplinary Research Project
from MEXT, and grants from the Ministry of Education, Culture, Sports, Science, and Technology of Japan. 相似文献
83.
Kim HJ Choi YS Jeong MJ Kim BO Lim SH Kim do K Kim CK Park JC 《Cell and tissue research》2007,327(1):25-31
Mutations in two genes, uncoordinated (unc) and uncoordinated-like (uncl), lead to a failure of mechanotransduction in Drosophila. UNCL, the human homolog of unc and uncl, is preferentially expressed in periodontal ligament (PDL) fibroblasts compared with gingival fibroblasts. However, the precise role of UNCL in the PDL remains unclear. The aim of the present study has been to examine whether mechanical stimuli modulate the expression of UNCL in the human PDL in vivo and in vitro and to examine the roles of UNCL in the development, regeneration, and repair of the PDL. We have investigated the expression pattern of UNCL during the development of periodontal tissue and the response of PDL fibroblasts to mechanical stress in vivo and in vitro. The expression of UNCL mRNA and protein increases with PDL fibroblast differentiation from the confluent to multilayer stage but slightly decreases on mineralized nodule formation. UNCL has also been localized in ameloblasts and adjacent cells, differentiating cementoblasts, and osteoblasts of the developing tooth. Strong distinct UNCL expression has further been observed in the differentiating cementoblasts of the tooth periodontium at the site of tension after orthodontic tooth movement. Application of cyclic mechanical stress on PDL fibroblasts increases the expression of UNCL mRNA. These results indicate that UNCL plays important roles in the development, differentiation, and maintenance of periodontal tissues and also suggest a potential role of UNCL in the mechanotransduction of PDL fibroblasts.This work was supported by a grant from the Korea Health 21R&D Project, Ministry of Health & Welfare, Republic of Korea (03-PJ1-PG1-CH08-0001). 相似文献
84.
Dorottya Frank Annamria Cser Bla Kolarovszki Nelli Farkas Attila Miseta Tams Nagy 《Journal of cellular and molecular medicine》2019,23(9):6251-6259
Protein O‐linked N‐acetylglucosamine (O‐GlcNAc) is a post‐translational modification of intracellular proteins that regulates several physiological and pathophysiological process, including response to various stressors. However, O‐GlcNAc's response to mechanical stress has not been investigated yet. As human periodontal ligament (PDL) cells are stimulated by compression force during orthodontic tooth movement that results in structural remodelling, in this study we investigated whether mechanical stress induces any alteration in protein O‐GlcNAc in PDL cells. In this study, PDL cells isolated from premolars extracted for orthodontic indications were exposed to 0, 1.5, 3, 7 and 14 g/cm2 compression forces for 12 hours. Cell viability was measured by flow cytometry, and protein O‐GlcNAc was analysed by Western blot. Cellular structure and intracellular distribution of O‐GlcNAc was studied by immunofluorescence microscopy. We found that between 1.5 and 3 g/cm2 mechanical compression, O‐GlcNAc significantly elevated; however, at higher forces O‐GlcNAc level was not increased. We also found that intracellular localization of O‐GlcNAc proteins became more centralized under 2 g/cm2 compression force. Our results suggest that structural changes stimulated by compression forces have a significant effect on the regulation of O‐GlcNAc; thus, it might play a role in the mechanical stress adaptation of PDL cells. 相似文献
85.
Cell surface integrin receptors mediate cell adhesion, migration and cellular signaling in all nucleated cells. They are activated by binding to extracellular ligands or by intracellular proteins, such as kindlins that engage with their cytoplasmic tails. Cells in the periodontal tissues express several integrins with overlapping ligand-binding capabilities. A distinct phenotype in the periodontium has only been described for knockouts or mutations of three integrin subunits, α11, β6 and β2. Integrin α11β1 appears to have some regulatory function in the periodontal ligament of continuously erupting incisors in mice. Integrin αvβ6 is expressed in the junctional epithelium (JE) of the gingiva. Animals deficient in this receptor develop classical signs of periodontal disease, including inflammation, apical migration of the JE and bone loss, suggesting that it plays a role in the regulation of periodontal inflmmation, likely through activation of transforming growth factor-β1. Lack of integrin activation in the JE is also associated with periodontitis. Patients with kindlin-1 mutations have severe early-onset periodontal disease. Finally, patients with mutations in the leukocyte-specific β2 integrin subunit have severe periodontal problems due to lack of transiting neutrophils in the periodontal tissues. 相似文献
86.
Jeremy D. Lin Jihyun Lee Hüseyin Özcoban Gerold A. Schneider Sunita P. Ho 《Journal of biomechanics》2014
In this study, an in vivo ligature-induced periodontitis rat model was used to investigate temporal changes to the solid and fluid phases of the joint by correlating shifts in joint biomechanics to adaptive changes in soft and hard tissue morphology and functional space. After 6 and 12 weeks of ligation, coronal regions showed a significant decrease in alveolar crest height, increased expression of TNF-α, and degradation of attachment fibers as indicated by decreased collagen birefringence. Cyclical compression to peak loads of 5–15 N at speeds of 0.2–2.0 mm/min followed by load relaxation tests showed decreased stiffness and reactionary load rate values, load relaxation, and load recoverability, of ligated joints. Shifts in joint stiffness and reactionary load rate increased with time while shifts in joint relaxation and recoverability decreased between control and ligated groups, complementing measurements of increased tooth displacement as evaluated through digital image correlation. Shifts in functional space between control and ligated joints were significantly increased at the interradicular (Δ10–25 μm) and distal coronal (Δ20–45 μm) regions. Histology revealed time-dependent increases in nuclei elongation within PDL cells and collagen fiber alignment, uncrimping, and directionality, in 12-week ligated joints compared to random orientation in 6-week ligated joints and to controls. We propose that altered strains from tooth hypermobility could cause varying degrees of solid-to-fluid compaction, alter dampening characteristics of the joint, and potentiate increased adaptation at the risk of joint failure. 相似文献
87.
本文通过甘肃临潭磨沟齐家文化墓地出土的262例人骨标本的牙病情况尤其是龋病、牙周病、根尖周病以及牙结石情况的统计与分析,得知磨沟墓地古代居民牙齿疾病的基本情况:1)牙病的罹患率性别差异显著,女性龋病和根尖周病的罹患率高于男性,而在牙周病和牙结石的出现率上则是男性高于女性;2)牙病的罹患率随着年龄增长而增高;3)龋病、牙周病及根尖周病多发于臼齿,牙结石多发于门齿;4)重度磨耗牙齿多发牙周病及根尖周病;5)牙病罹患率不仅受到性别、年龄、牙位以及齿冠磨耗程度的影响,而且与磨沟组古代居民农业种植食物和采集食物并重的食物结构有关。 相似文献
88.
牙周再生膜体外降解的实验研究 总被引:1,自引:0,他引:1
张海华 《上海生物医学工程》2005,26(1):28-32
目的研究牙周再生膜在体外动态和静态降解体系中的降解性能。方法用聚乳酸乙醇酸制作的牙周再生膜在动态(降解介质流速为250μl/min)和静态两种降解体系中进行降解,分别在材料降解前的第0周和降解后的第1、2、4、6周测定牙周再生膜在体外动态和静态降解体系中的残存质量、平均分子量、弹性模量、孔隙率和渗透性的变化并对两种降解体系中的降解性能进行比较。结果降解过程中,牙周再生膜实验材料的质量随着降解的进行而不断损耗,残存的质量越来越少。实验材料的分子量随着降解的进行而不断减少。牙周再生膜的质量和分子量在静态降解体系中损失速度显著高于在动态降解体系(P<0.01);在两种实验条件下,牙周再生膜实验材料的弹性模量都是在第2周时开始上升,随后下降。材料的弹性模量在动态降解体系中较之静态降解体系能维持较长时间;无论在动态降解条件下,还是在静态降解条件下,实验材料的孔隙率都是从第2周时开始下降,而后逐渐增加。降解系统的状态对材料孔隙率变化的影响无显著差异(P>0.05);材料在静态降解体系中的渗透性显著高于动态降解体系(P<0.01)。材料在两种降解介质中的降解性能相似,但是在所测定的降解指标中,材料在人工唾液中的变化速度显著高于在PBS中的(0.01