Modifi cation of β-TCP/PLGA Scaffold and Its Effect on Bone Regeneration in vivo

In order to look for the best proportion of β-tricalcium phosphate（β-TCP）and poly（lactideco-glycolide）（PLGA）we fabricated porous composites β-TCP/PLGA scaffold using freeze-drying method.Morphologicalcharacterization using scanning electron microscopy showed that the interconnected pore distribution was even and there was no significant difference with the increase of PLGA content.Moreover,the porosity,compressive strength and degradation in vitro were characterized.The fabricated scaffolds with increased PLGA in the composites β-TCP/PLGA scaffolds willget stronger mechanicalproperty and better appearance,furthermore,get suitable environment for cells.According to the evaluation indexes for the tissue engineering scaffold,the group of scaffold（β-TCP/PLGA=6：4）was selected to evaluate the induced celladhesion and proliferative ability of the scaffolds.Then as transplant embed into the bone criticaldefect sites on rats femur.The repairing processes of bone defect sites were characterized by X-ray analysis within 12 weeks.X-ray analysis showed that the bone defect sites alldisplayed the formation of callus obviously,In summary,our data suggest that the scaffold（β-TCP/PLGA=6：4）has a promising clinicalfuture in regeneration of bone criticaldefects.

Computed tomography perfusion and computed tomography angiography for prediction of clinical outcomes in ischemic stroke patients after thrombolysis

Cerebral blood perfusion and cerebrovascular lesions are important factors that can affect the therapeutic efficacy of thrombolysis.At present,the majority of studies focus on assessing the accuracy of lesion location using imaging methods before treatment,with less attention to predictions of outcomes after thrombolysis.Thus,in the present study,we assessed the efficacy of combined computed tomography（CT） perfusion and CT angiography in predicting clinical outcomes after thrombolysis in ischemic stroke patients.The study included 52 patients who received both CT perfusion and CT angiography.Patients were grouped based on the following criteria to compare clinical outcomes：（1） thrombolytic and non-thrombolytic patients,（2） thrombolytic patients with CT angiography showing the presence or absence of a vascular stenosis,（3） thrombolytic patients with CT perfusion showing the presence or absence of hemodynamic mismatch,and（4） different CT angiography and CT perfusion results.Short-term outcome was assessed by the 24-hour National Institution of Health Stroke Scale score change.Long-term outcome was assessed by the 3-month modified Rankin Scale score.Of 52 ischemic stroke patients,29 were treated with thrombolysis and exhibited improved short-term outcomes compared with those without thrombolysis treatment（23 patients）.Patients with both vascular stenosis and blood flow mismatch（13 patients） exhibited the best short-term outcome,while there was no correlation of long-term outcome with CT angiography or CT perfusion findings.These data suggest that combined CT perfusion and CT angiography are useful for predicting short-term outcome,but not long-term outcome,after thrombolysis.