Effectiveness of radiation synovectomy with samarium-153 particulate hydroxyapatite in rheumatoid arthritis patients with knee synovitis: a controlled randomized double-blind trial

OBJECTIVES: The aim of the present study was to investigate the effectiveness of Samarium153-particulate hydroxyapatite radiation synovectomy in rheumatoid arthritis patients with chronic knee synovitis. METHODS: Fifty-eight rheumatoid arthritis patients (60 knees) with chronic knee synovitis participated in a controlled double-blinded trial. Patients were randomized to receive either an intra-articular injection with 40 mg triamcinolone hexacetonide alone (TH group) or 40 mg triamcinolone hexacetonide combined with 15 mCi Samarium153-particulate hydroxyapatite (Sm/TH group). Blinded examination at baseline (T0) and at 1 (T1), 4 (T4), 12 (T12), 32 (T32), and 48 (T48) weeks post-intervention were performed on all patients and included a visual analog scale for joint pain and swelling as well as data on morning stiffness, flexion, extension, knee circumference, Likert scale of improvement, percentage of improvement, SF-36 generic quality of life questionnaire, Stanford Health Assessment Questionnaire (HAQ), Lequesne index, use of non-steroidal anti-inflammatory drugs or oral corticosteroids, events and adverse effects, calls to the physician, and hospital visits. RESULTS: The sample was homogeneous at baseline, and there were no withdrawals. Improvement was observed in both groups in relation to T0, but no statistically significant differences between groups were observed regarding all variables at the time points studied. The Sm/TH group exhibited more adverse effects at T1 (p<0.05), but these were mild and transitory. No severe adverse effects were reported during follow-up. CONCLUSION: Intra-articular injection of Samarium153-particulate hydroxyapatite (15 mCi) with 40 mg of triamcinolone hexacetonide is not superior to triamcinolone hexacetonide alone for the treatment of knee synovitis in patients with rheumatoid arthritis at 1 y of follow-up.

Avaliaçäo do comportamento biológico de dois materiais sintéticos, à base de fosfato de cálcio (Biohapatita R e Osteogem R) após a implantaçäo em alvéolos de cäes / Evaluation of the biologic behavior of two synthetic materials of calcium-phosphate (Biohapatita R and OsteoGen R) implanted in dog's sockets

Este trabalho tem por objetivo avaliar o comportamento biológico de dois materiais sintéticos (OsteoGen R e Biohapatita R), implantados em alvéolos de cäes. Para tanto foram extraídos todos os pré-molares inferiores de 4 cäes, sendo os alvéolos preenchidos com um dos implantes acima, a exceçäo dos pertencentes ao grupo controle, que näo receberam nenhum material. A análise histológica mostrou que a Biohapatita apresentou a maioria de seus cristais envoltos por tecido conjuntivo, com pequena quantidade de formaçäo óssea, enquanto o OsteoGen apresentou formaçäo óssea direta na superfície dos seus cristais. Poucos cristais de Biohapatita permaneceram nos espécimes analisados, enquanto, em relaçäo ao OsteoGen, um grande número de cristais estava presente

Avaliaçäo da taxa de dissoluçäo de hidroxiapatias preparadas em diferentes condiçöes / Evaluation of dissolution rate of hidroxyapatite prepared in different conditions

A solubilidade dos vários compostos da família dos fosfatos de cálcio no meio fisiológico é uma das principais características utilizadas para a escolha do composto mais adequado para cada aplicação. Para um mesmo composto, entretanto, a solubilidade pode variar devido a variação da concentração de defeitos, a área superficial. a razão Ca/P, o tamanho de particulas, outros tipos e quantidade de fases presentes e porosidade. O objetivo do presente trabalho foi estudar um método que permite avaliar comparativamente a solubilidade de hidroxiapatitas com caracteristicas diferentes. Os resultados obtidos demonstram a eficácia do método proposto para avaliar a solubilidade da hidroxiapatita e confirmam a interrelação entre a solubilidade, a razão Ca/P e a presença de grupos CO3**-2 detectada pela espectroscopia de infravermelho

Abstract - The solubility of the various compounds of the calcium phosphate family in the physiological medium is one of the main characteristics used to identify the most suitable compound for each application. However. for one single compound the solubility may vary due to the concentration of defects. The objective of this work was to develop a method which would allow us to evaluate comparatively the solubility of hydroxyapatites with different characteristics. The results obtained have shown that the proposed method is suitable to evaluate the solubility of hydroxyapatite and have confirmed the relationship between solubility, the Ca/P ratio and the presence of CO/ groups detected by infrared spectroscopy