Avaliação da eficácia do sistema rigeneracon no tratamento de lesões de calvária em ratos / [Evaluation of the efficacy of the rigeneracon system in the treatment of calvary injuries in rats]

Defeitos ósseos constituem um problema de saúde global. O sistema Rigenera permite a extração de microenxertos ricos em células-tronco mesenquimais (CTMs). Objetivou-se avaliar o processo de regeneração óssea por enxertos obtidos pelo sistema Rigenera em defeitos críticos na calvária de ratos. Foram utilizados 18 ratos Wistar, machos, pesando 285±29g, distribuídos em três grupos (n=6), sendo cada animal controle de si mesmo, denominados G15-Controle e G15-Tratado (15 dias); G30-Controle e G30-Tratado (30 dias) e G60-Controle e G60-Tratado (60 dias). Foram realizadas duas lesões de 5mm de diâmetro em cada antímero da calvária. Nos grupos tratados, foram utilizados microenxertos autólogos de cartilagem xifoide, obtidos pelo sistema Rigenera. O defeito contralateral serviu como controle em todos os animais. Os animais foram eutanasiados aos 15, 30 e 60 dias após a cirurgia, e as amostras foram processadas para a histoquímica. Nos grupos controle, não foram observados sinais de regeneração óssea, enquanto nos grupos tratamento foram verificadas áreas de formação óssea e tecido mesenquimal ativado. O sistema Rigenera foi eficiente na obtenção de microenxertos autólogos, para terapia celular em defeito crítico de calvária de ratos. Com o aprimoramento do protocolo, o sistema Rigenera poderá ser amplamente utilizado no tratamento de lesões ósseas.(AU)

Bone defects are a global health problem. The Rigenera system allows the extraction of micro grafts rich in mesenchymal stem cells (MSCs). The objective of this study was to evaluate the bone regeneration process by grafts obtained by the Rigenera system in defects in the rats calvarian. Eighteen male Wistar rats were used, weighing 285 ± 29g, distributed in three groups (n = 6), where each animal was treatment and control, called G15-Control and G15-Treated (15 days); G30-Control and G30-Treated (30 days) and G60-Control and G60-Treated (60 days). Two 5mm diameter lesions were performed on each calvaria side. In the treated groups, autologous micrograft from xiphoid cartilage, obtained by the Rigenera system, were used. The other defect served as a control in all animals. The animals were euthanized at 15, 30 and 60 days after the surgery and the samples were processed for histochemistry. In the control groups, no signs of bone regeneration were observed, while in the treatment groups, areas of bone formation and activated mesenchymal tissue were verified. The Rigenera system was efficient in obtaining autologous micrograft for cell therapy in a critical calvaria defect in rats. Rigenera system can be widely used in the treatment of bone injuries.(AU)

Effect of oral sirolimus therapy on inflammatory biomarkers following coronary stenting

We studied the effect of oral sirolimus, administered to prevent and treat in-stent restenosis (ISR), on the variation of serum levels of inflammatory markers following coronary stenting with bare metal stents. The mean age of the patients was 56 ± 13 years, 65 percent were males and all had clinically manifested ischemia. Serum levels of high sensitivity C-reactive protein (hs-CRP) concentration were determined by chemiluminescence and serum levels of all other biomarkers by ELISA. One group of patients at high risk for ISR received a loading oral dose of 15 mg sirolimus and 5 mg daily thereafter for 28 days after stenting (SIR-G). A control group (CONT-G) was submitted to stenting without sirolimus therapy. The increase in hs-CRP concentration was highest at 24 h after stenting in both groups. A significant difference between SIR-G and CONT-G was observed at 4 weeks (-1.50 ± 5.0 vs -0.19 ± 0.4, P = 0.008) and lost significance 1 month after sirolimus discontinuation (-1.73 ± 4.3 vs -0.01 ± 0.7, P = 0.0975). A continuous fall in MMP-9 concentration was observed in SIR-G, with the greatest reduction at 4 weeks (-352.9 ± 455 vs +395.2 ± 377, P = 0.0004), while a positive variation was noted 4 weeks after sirolimus discontinuation (227 ± 708 vs 406.2 ± 472.1, P = 0.0958). SIR-G exhibited a higher increase in P-selectin after sirolimus discontinuation at week 8 (46.1 ± 67.9 vs 5.8 ± 23.7, P = 0.0025). These findings suggest that the anti-restenotic actions of systemic sirolimus include anti-proliferative effects and modulation of the inflammatory response with inhibition of adhesion molecule expression.