910 resultados para BONE HEALTH
Resumo:
The aim of this study was to evaluate the healing of class III furcation defects following transplantation of autogenous periosteal cells combined with b-tricalcium phosphate (b-TCP). Periosteal cells obtained from Beagle dogs’ periosteum explant cultures, were inoculated onto the surface of b-TCP. Class III furcation defects were created in the mandibular premolars. Three experimental groups were used to test the defects’ healing: group A, b-TCP seeded with periosteal cells were transplanted into the defects; group B, b-TCP alone was used for defect filling; and group C, the defect was without filling materials. Twelve weeks post surgery, the tissue samples were collected for histology, immunohistology and X-ray examination. It was found that both the length of newly formed periodontal ligament and the area of newly formed alveolar bone in group A, were significantly increased compared with both group B and C. Furthermore, both the proportion of newly formed periodontal ligament and newly formed alveolar bone in group A were much higher than those of group B and C. The quantity of cementum and its percentage in the defects (group A) were also significantly higher than those of group C. These results indicate that autogenous periosteal cells combined with b-TCP application can improve periodontal tissue regeneration in class III furcation defects.
Resumo:
The pore architecture of scaffolds is known to play a critical role in tissue engineering as it provides the vital framework for seeded cells to organize into a functioning tissue. In this report we have investigated the effects of different concentrations of silk fibroin protein on three-dimensional (3D) scaffold pore microstructure. Four pore size ranges of silk fibroin scaffolds were made by the freeze drying technique, with the pore sizes ranging from 50 to 300 lm. The pore sizes of the scaffolds decreased as the concentration of fibroin protein increased. Human bone marrow mesenchymal stromal cells (BMSC) transfected with the BMP7 gene were cultured in these scaffolds. A cell viability colorimetric assay, alkaline phosphatase assay and reverse transcription-polymerase chain reaction were performed to analyze the effect of pore size on cell growth, the secretion of extracellular matrix (ECM) and osteogenic differentiation. Cell migration in 3D scaffolds was confirmed by confocal microscopy. Calvarial defects in SCID mice were used to determine the bone forming ability of the silk fibroin scaffolds incorporating BMSC expressing BMP7. The results showed that BMSC expressing BMP7 preferred a pore size between 100 and 300 lm in silk fibroin protein fabricated scaffolds, with better cell proliferation and ECM production. Furthermore, in vivo transplantation of the silk fibroin scaffolds combined with BMSC expressing BMP7 induced new bone formation. This study has shown that an optimized pore architecture of silk fibroin scaffolds can modulate the bioactivity of BMP7-transfected BMSC in bone formation.
Resumo:
Structural health is a vital aspect of infrastructure sustainability. As a part of a vital infrastructure and transportation network, bridge structures must function safely at all times. However, due to heavier and faster moving vehicular loads and function adjustment, such as Busway accommodation, many bridges are now operating at an overload beyond their design capacity. Additionally, the huge renovation and replacement costs are a difficult burden for infrastructure owners. The structural health monitoring (SHM) systems proposed recently are incorporated with vibration-based damage detection techniques, statistical methods and signal processing techniques and have been regarded as efficient and economical ways to assess bridge condition and foresee probable costly failures. In this chapter, the recent developments in damage detection and condition assessment techniques based on vibration-based damage detection and statistical methods are reviewed. The vibration-based damage detection methods based on changes in natural frequencies, curvature or strain modes, modal strain energy, dynamic flexibility, artificial neural networks, before and after damage, and other signal processing methods such as Wavelet techniques, empirical mode decomposition and Hilbert spectrum methods are discussed in this chapter.
Resumo:
This article provides a critical review of the literature relevant to the conceptual foundations of health promoting palliative care. It explores the separate emergence and evolution of palliative care and health promotion as distinct concerns in health care, and reviews the early considerations given to their potential convergence. Finally, this article examines the proposal of health promoting palliative care as a specific approach to providing end of life care through a social model of palliative care. Research is needed to explore the impact for communities, health care services and policy when such an approach is implemented within palliative care organisations.
Resumo:
Four studies report on outcomes for long-term unemployed individuals who attend occupational skills/personal development training courses in Australia. Levels of distress, depression, guilt, anger, helplessness, positive and negative affect, life satisfaction and self esteem were used as measures of well-being. Employment value, employment expectations and employment commitment were used as measures of work attitude. Social support, financial strain, and use of community resources were used as measures of life situation. Other variables investigated were causal attribution, unemployment blame, levels of coping, self efficacy, the personality variable of neuroticism, the psycho-social climate of the training course, and changes to occupational status. Training courses were (a) government funded occupational skills-based programs which included some components of personal development training, and (b) a specially developed course which focused exclusively on improving well-being, and which utilised the cognitive-behavioural therapy (CBT) approach. Data for all studies were collected longitudinally by having subjects complete questionnaires pre-course, post-course, and (for 3 of the 4 studies) at 3 months follow-up, in order to investigate long-term effects. One of the studies utilised the case-study methodology and was designed to be illustrative and assist in interpreting the quantitative data from the other 3 evaluations. The outcomes for participants were contrasted with control subjects who met the same sel~tion criteria for training. Results confirmed earlier findings that the experiences of unemployment were negative. Immediate effects of the courses were to improve well-being. Improvements were greater for those who attended courses with higher levels of personal development input, and the best results were obtained from the specially developed CBT program. Participants who had lower levels of well-being at the beginning of the courses did better as a result of training than those who were already functioning at higher levels. Course participants gained only marginal advantages over control subjects in relation to improving their occupational status. Many of the short term well-being gains made as a result of attending the courses were still evident at 3 months follow-up. Best results were achieved for the specially designed CBT program. Results were discussed in the context of prevailing theories of Ynemployment (Fryer, 1986,1988; Jahoda, 1981, 1982; Warr, 1987a, 1987b).