Influence of simvastatin on bone regeneration of tibial defects and blood cholesterol level in rats

The purpose of this study was to evaluate the effects of simvastatin, by oral or subcutaneous administration, on tibial defects regeneration and blood cholesterol level in rats. A surgical defect was made on the right tibia of 40 male animals assigned to 4 groups (n=10), based on two routes of administration and on the use or not of simvastatin: subcutaneous injection of simvastatin (7 mg/kg) (group AT) or only the vehicle of drug suspension (group AC), above the defect area, for 5 days; and 20 mg/kg of simvastatin macerated on water (group BT) or only water (group BC), orally, daily, during the whole observation period. The animals were sacrificed after 15 or 30 days, when blood samples were analyzed to check plasma cholesterol levels. Tibiae were removed and, after decalcification and routine laboratorial processing, histological and histomorphometrical analyses were carried out. ANOVA was used for statistical analysis at 5 percent signficance level. The histological and histomorphometrical analyses showed significant differences only between the experimental periods (p<0.05). Animals sacrificed after 30 days showed better bone repair (p<0.05). There was no statistically significant difference (p>0.05) for blood cholesterol levels between the groups. In conclusion, simvastatin administration either orally or subcutaneously did not improve bone repair of experimental tibial defects and did not alter blood cholesterol levels in rats.

Este estudo avaliou a influência da sinvastatina, administrada por via oral ou subcutânea, na reparação de defeitos ósseos em tíbia e nos níveis de colesterol sangüíneo, em ratos. Foram realizados defeitos cirúrgicos nas tíbias direitas de 40 ratos machos, distribuídos em 4 grupos (n=10), tomando-se como base duas vias de administração e o uso ou não de sinvastatina: injeção subcutânea de sinvastatina (7 mg/kg) (grupo AT) ou apenas do veículo de suspensão da droga (grupo AC), sobre a região do defeito, durante 5 dias; 20 mg/kg de sinvastatina (grupo BT) ou água filtrada (grupo BC) via oral, diariamente, durante todo o período de observação. Os animais foram sacrificados após 15 ou 30 dias, quando amostras sangüíneas foram colhidas para análise do nível de colesterol. As tíbias foram removidas e, após descalcificação e procedimentos laboratoriais de rotina, procedeu-se à análise histológica e histomorfométrica. Para avaliação estatística utilizou-se ANOVA com nível de significância de 5 por cento. As análises histomorfométrica e histológica mostraram diferença entre os grupos apenas com relação ao período experimental (p<0,05), apresentando os melhores resultados os animais sacrificados em 30 dias (p<0,05). Quanto ao nível de colesterol sangüíneo, não houve diferença estatisticamente significante entre os grupos analisados (p>0,05). Concluiu-se que, nas condições utilizadas, a sinvastatina, administrada via oral ou subcutânea, não exerceu efeito estimulador sobre o reparo ósseo de defeitos experimentais em tíbias de ratos e não alterou os níveis de colesterol sangüíneo.

Comparación de la eficacia clínica de una inyección intraarticular o intralesional de dos preparados de betametasona en pacientes con artrosis o epicondilitis / Comparative effects of intra articular injections of two betametasone preparations in patients with osteoarthritis or epicondilytis

Background: Local infiltration with corticoids is a simple therapy for rheumatic disorders devoid of systemic adverse reactions. Aim: To compare the efficacy of two betametasone preparations from two different pharmaceutical laboratories in the treatment of patients with osteoarthritis or epicondilytis. Patients and methods: Fourty patients with knee osteoarthritis and 12 patients with epicondilytis were studied. Using a double blind protocol, one of the two betametasone preparations was used for local infiltration of the lesions. The change in a global score of clinical variables including pain and disability was assessed after 30 days of the infiltration. Results: In patients with osteoarthritis, the global score decreased significantly with both preparations, but no differences were observed between preparations (7.3ñ1.8 to 3.9ñ2.3 with preparation A and 7.8ñ1.9 to 3.6ñ2.3 with preparation B). In patients with epicondilytis, pain was also significantly reduced but no differences between preparations was observed (7ñ2.1 to 1.4ñ2.5 for preparation A and 4.6ñ2.8 to 1.2ñ1.6 for preparation B). Conclusions: Local infiltration with both betametasone preparations was equally effective in the treatment of patients with knee osteoarthritis or epicondilytis

Crecimiento in vitro de periostio

A partir de 1987, en la Universidad del Valle, se comienzan a implementar técnicas de cultivo celular y de análisis histológico, en microscopio de luz y en microscopio de barrido, para el estudio de muestas de periostio. Se emplearon conejos Nueva Zelanda y ovejos africanos como animales de experimentación. Se observó crecimiento de fibroblastos y de células mesenquimatosas. Cuando estas células eran mantenidas durante períodos mayores a dos semanas en el mismo medio de cultivo, presentaban fenómenos de envejecimiento, debido al déficit regional de sustratos. Su reactivación con obtención de la morfología inicial, fue posible mediante siembras sucesivas, a partir de una monocapa del cultivo saturado. El principal riesgo de inhibición del crecimiento o muerte celular, se relaciona con la contaminación micótica y/o bacteriana. Las técnicas de cultivo celular, se constituyen en un elemento útil y abren nuevas perspectivas en la reparación de lesiones osteoarticulares preexistentes de origen traumático, infeccioso, degenerativo o congénito