In vivo tissue distribution of hydroxyapatite nanoparticles modified with aminopropyltriethoxysilane / 中国药学杂志

OBJECTIVE: To investigate the in vivo tissue distribution of hydroxyapatite nanoparticles (HANPs) and provide important information for the in vivo biosafety evaluation of HANPs. METHODS: The HANPs were modified with aminopropyltriethoxysilane (APTS) to introduce amino groups on the surface. The modified HANPs were labeled with 125I and injected into mice. A γ-counter was used to quantitatively assess the radioactivity of the tissues. The accumulation of HANPs in the tissues was expressed as the percentage injected dose per gram tissue (%ID · g-1). RESULTS: The HANPs mainly accumulated in the lung, liver, and spleen. One day post-injection, the accumulation in these tissues was over 5% ID · g-1. During 30 d after the injection, the accumulation of HANPs in the lung decreased quickly, while the accumulation in the liver and spleen reduced moderately and maintained at more than 2% ID · g-1. CONCLUSION: This study indicates that lung, liver and spleen are the main tissues for the in vivo biosafety evaluation of HANPs. KEY

Effect of occlusal reconstruction on cerebral blood flow and cerebral oxygen saturation in patients with malocclusion / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the effect of occlusal reconstruction on blood flow velocity and cerebral oxygen saturation in patients with malocclusion.</p><p><b>METHODS</b>Thirty-three patients with malocclusion treated with occlusal reconstruction in Department of Stomatology, Medical School of Huzhou Normal College from Feb 2011 to Oct 2013 were enrolled in the study. The systolic peak flow velocity (vs), end-diastolic peak flow (vd) , mean peak flow velocity (vm) of middle cerebral artery and the oxygen saturation (rScO2) in the brain were detected at rest or chewing status by using transcranial Doppler color ultrasonography and near-infrared spectroscopy, respectively.</p><p><b>RESULTS</b>In rest state, vm was significantly increased on 3 months after treatment, while vs and vd were significantly increased on 6 months after treatment and rScO2 were increased on 12 months after treatment (P<0.05). In chewing state, vs, vm, and rScO2 were increased on 3 months after treatment, and vd was increased on 6 months after treatment (P<0.05).</p><p><b>CONCLUSION</b>Occlusal reconstruction can increase blood flow velocity of middle cerebral artery and cerebral oxygen saturation and improve oxygen supply of the brain in patients with malocclusion.</p>