Induction of abundant osteoclast-like multinucleated giant cells in adjuvant arthritic rats with accompanying disordered high bone turnover

The development of an in vivo system for investigating osteoclast differentiation is important because molecular events occurring in vivo can be observed during the differentiation of the authentic osteoclasts. In adjuvant arthritic rats, an experimental model of human rheumatoid arthritis, extensive bone resorption is observed in the distal diaphysis of the tibia. In the area of extensive bone resorption, it is always accompanied with clusters of numerous multinucleated giant cells (MGCs) as well as bone-resorbing osteoclasts. Here we characterized the morphological properties of these MGCs with the use of enzymehistochemical and immunohistochemical techniques. Extensive destruction but also a marked formation of the inner and outer bone surfaces were the predominant features in the tibiae of such arthritic rats 4 weeks after the adjuvant injection. Numerous MGCs were frequently clustered in the bone marrow spaces located apart from the bone matrices. Although the MGCs lacked ruffled borders, these cells were rich in mitochondria and vacuoles. These multinucleated cells revealed a positive reaction for tartrate-resistant acid phosphatase but a negative reaction for non-specific esterase staining. Most of these MGCs expressed the Kat l-antigen, an immunological marker specifically expressed on the cell surface of rat osteoclasts. In a dentin resorption experiment using a cluster of MGCs excised from the bone marrow tissues of the tibial distal diaphyses of rats with adjuvant arthritis, many resorption lacunae were formed on dentin slices after a 3-day culture. These results suggest that the majority of the MGCs are osteoclasts but not macrophage polykaryons

Effects of static magnetic fields on bone formation in rat osteoblast cultures

Although the promotional effects on osteoblasts of pulsed electromagnetic fields have been well-demonstrated, the effects of static magnetic fields (SMF) remain unclear; nevertheless, magnets have been clinically used as a 'force source' in various orthodontic treatments. We undertook the present investigation to study the effects of SMF on osteoblastic differentiation, proliferation, and bone nodule formation using a rat calvaria cell culture. During a 20-day culture, the values of the total area and the number and average size of bone nodules showed high levels in the presence of SMF. In the matrix development and mineralization stages, the calcium content in the matrix and two markers of osteoblastic phenotype (alkaline phosphatase and osteocalcin) also showed a significant increase. Accordingly, these findings suggest that SMF stimulates bone formation by promoting osteoblastic differentiation and/or activation.link_to_subscribed_fulltex

Induction of abundant osteoclast-like multinucleated giant cells in adjuvant arthritic rats with accompanying disordered high bone turnover

The development of an in vivo system for investigating osteoclast differentiation is important because molecular events occurring in vivo can be observed during the differentiation of the authentic osteoclasts. In adjuvant arthritic rats, an experimental model of human rheumatoid arthritis, extensive bone resorption is observed in the distal diaphysis of the tibia. In the area of extensive bone resorption, it is always accompanied with clusters of numerous multinucleated giant cells (MGCs) as well as bone-resorbing osteoclasts. Here we characterized the morphological properties of these MGCs with the use of enzymehistochemical and immunohistochemical techniques. Extensive destruction but also a marked formation of the inner and outer bone surfaces were the predominant features in the tibiae of such arthritic rats 4 weeks after the adjuvant injection. Numerous MGCs were frequently clustered in the bone marrow spaces located apart from the bone matrices. Although the MGCs lacked ruffled borders, these cells were rich in mitochondria and vacuoles. These multinucleated cells revealed a positive reaction for tartrate-resistant acid phosphatase but a negative reaction for non-specific esterase staining. Most of these MGCs expressed the Kat l-antigen, an immunological marker specifically expressed on the cell surface of rat osteoclasts. In a dentin resorption experiment using a cluster of MGCs excised from the bone marrow tissues of the tibial distal diaphyses of rats with adjuvant arthritis, many resorption lacunae were formed on dentin slices after a 3-day culture. These results suggest that the majority of the MGCs are osteoclasts but not macrophage polykaryon

A 3-dimensional method for analyzing facial soft-tissue morphology of patients with jaw deformities

Introduction: Traditional cephalometric radiographs can analyze facial soft-tissues 2 dimensionally. Because they cannot provide information about the nose, lips, cheeks, and mouth, another method is needed to analyze these soft tissues. We introduce a new method for analyzing the 3-dimensional (3D) shape and size of facial soft-tissue morphology. Methods: A 3D average face model was constructed based on 3D computed tomography images of Japanese male and female adult volunteers who had well-balanced faces and normal occlusions. To test the feasibility of evaluating the quantitative effects of surgery, preoperative and postoperative 3D computed tomography images of facial soft tissues of 1 man and 1 woman were superimposed on the average faces. Results: This quantitative assessment provided a comprehensive evaluation of the characteristics that separate size and shape. It was possible to view the superimposed images from any desired angle on a personal computer. Conclusions: This method provides easy-to-understand information for patients and appears to be useful for clinical diagnosis and pretreatment and posttreatment soft-tissue morphologic evaluations of patients with jaw deformities. © 2009 American Association of Orthodontists.link_to_subscribed_fulltex

Relationship between the unilateral TMJ osteoarthritis/osteoarthrosis, mandibular asymmetry and the EMG activity of the masticatory muscles: A retrospective study

The purpose of this retrospective study was to investigate the relationship between the unilateral temporomandibular joint (TMJ) osteoarthritis/ osteoarthrosis (OA), mandibular asymmetry and electromyographic (EMG) activity of the masticatory muscles. Twenty-two Japanese women (aged 23·2 ± 5·4 years) and 10 Japanese men (aged 22·4 ± 2·8 years) exhibiting unilateral TMJ OA were included in this study. Two angular and seven linear measurements were obtained for the analysis of the skeletal hard tissues. The cephalometric measurement values (CV) were normalized using the CV ratio for the evaluation of the degree of mandibular asymmetry. The EMG was recorded during maximal voluntary clenching efforts for 10 s in the intercuspal position. The average values of integral EMG (iEMG) of three trials were normalized using the iEMG ratio for the evaluation of the functional balance of the masticatory muscles. The mandibular midline was shifted to the TMJ OA side with a median value of 9·85 mm. The CV ratio of the ramus height of the TMJ OA side was significantly smaller than that of the non-OA side. For the masseter muscle, the iEMG ratio of the TMJ OA side was significantly larger than that of the non-OA side (P < 0·05). These results suggest that unilateral TMJ OA is related to the dentofacial morphology, thus resulting in a mandibular midline shift to the affected side and it is associated with a masticatory muscle imbalance. © 2009 Blackwell Publishing Ltd.link_to_subscribed_fulltex

An approach on the implementation of full batch, online and mini-batch learning on a Mamdani based neuro-fuzzy system with center-of-sets defuzzification: Analysis and evaluation about its functionality, performance, and behavior.

Due to the rapid technological evolution and communications accessibility, data generated from different sources of information show an exponential growth behavior. That is, volume of data samples that need to be analyzed are getting larger, so the methods for its processing have to adapt to this condition, focusing mainly on ensuring the computation is efficient, especially when the analysis tools are based on computational intelligence techniques. As we know, if you do not have a good control of the handling of the volume of the data, some techniques that are based on learning iterative processes could represent an excessive load of computation and could take a prohibitive time in trying to find a solution that could not come close to desired. There are learning methods known as full batch, online and mini-batch, and they represent a good strategy to this problem since they are oriented to the processing of data according to the size or volume of available data samples that require analysis. In this first approach, synthetic datasets with a small and medium volume were used, since the main objective is to define its implementation and in experimentation phase through regression analysis obtain information that allows us to assess the performance and behavior of different learning methods under distinct conditions. To carry out this study, a Mamdani based neuro-fuzzy system with center-of-sets defuzzification with support of multiple inputs and outputs was designed and implemented that had the flexibility to use any of the three learning methods, which were implemented within the training process. Finally, results show that the learning method with best performances was Mini-Batch when compared to full batch and online learning methods. The results obtained by mini-batch learning method are as follows; mean correlation coefficient [Formula: see text] with 0.8268 and coefficient of determination [Formula: see text] with 0.7444, and is also the method with better control of the dispersion between the results obtained from the 30 experiments executed per each dataset processed

TMJ osteoarthritis/osteoarthrosis and dentofacial morphology in Japanese females

The temporomandibular joint (TMJ) is the principal adaptive center for determining the intermaxillary relationship in all three planes of space. The joint diseases, such as TMJ osteoarthritis/osteoarthrosis (OA) might associate with dentofacial morphologic changes. The purpose of this study was to investigate the relationship between TMJ OA and dentofacial morphology in Japanese females and compare findings to a normal control group. The subjects consisted of 24 Japanese females with TMJ OA (aged 22.5 ± 4.4 years) and a control group of 24 asymptomatic Japanese females (aged 23.6 ± 1.3 years). Linear and angular cephalometric measurements were noted to evaluate the skeletal, dental and soft tissue relationships of the two groups. Unpaired t-tests were used to compare the mean differences of each cephalometric measurement between the TMJ OA and the control group. The subjects with TMJ OA had a more significant posteriorly rotated mandible as well as a smaller mandible compared with the subjects in the control group. They also had more protrusive lower incisors, upper lips and lower lips. These results suggest that there might exist association between TMJ OA and dentofacial morphology in Japanese females. © 2006 Elsevier Ltd and the Japanese Orthodontic Society.link_to_subscribed_fulltex

A 3-dimensional method for analyzing the morphology of patients with maxillofacial deformities

Introduction: Traditionally, cephalograms have been used to evaluate a patient's maxillofacial skeleton and facial soft-tissue morphology. However, magnification and distortion of the cephalograms make detailed morphologic analysis difficult in patients with complex deformities. The purpose of this article was to introduce a new method for visualizing deformation and deviation of the maxillofacial skeleton and facial soft tissues. Methods: Standard 3-dimensional Japanese head models were sized to match the sella-to-nasion distance obtained from 2 patients' (1 man, 1 woman) maxillofacial skeletal images. Then, the scaled standard model was superimposed on each patient's 3-dimensional computed tomography image. Results: This system provided clear shape information independent of size and facilitated the visualization of shape variations in maxillofacial skeletal and facial soft-tissue morphology. Conclusions: This method will be useful for 3-dimensional morphologic analysis of patients with jaw deformities. © 2009 American Association of Orthodontists.link_to_subscribed_fulltex