ABSTRACT
OBJECTIVE:To prepare theophylline pulsed suppository(TPS)and evaluate its in vitro release characteristics.METHODS:The formulation of TPS was optimized using single factor method taking the amount of base materials including poloxamer,CMC-Na,PEG 6000 and PEG 400 as factors with lag time of drug release and the accumulative drug release rate served as indexes.The accumulative drug release rates of the TPS prepared with different fillers(crude drug of theopylline,theopylline-PVP physical mixture,and the theopylline-PVP solid dispersion)were investigated.RESULTS:The optimal formulation was as follows:70% poloxamer,6% CMC-Na,12% PEG 6000,12% PEG 400;its lag time of in vitro drug release was about 4 hours and its accumulative drug release rate at 90 min reached more than 85%.The accumulative drug release rates of the suppository prepared with 3 different fillers were 58.8%,65.8% and 91%,respectively.CONCLUSION:The prepared TPS showed satisfactory pulsed release efficacy.
ABSTRACT
Objective To evaluate the immediate results and the 6 month angiographic restenosis rate after repeat percutaneous intervention for in stent restenosis (ISR) Methods The acute and 6 month follow up outcomes of 156 patients with ISR who were treated by repeat PTCA or stenting were analyzed in this retrospective study Quantitative coronary angiography analyses (QCA) were performed before and after repeat intervention for in stent restenosis and on a average 6 month coronary angiogram to assess the recurrent restenosis rate Results All the patients were treated successfully Balloon angioplasty was performed in 134 patients (85 9%) and repeat stenting in 22 patients (14 1%) The six month follow up coronary angiogram showed the recurrent restenosis rate was 24 3% The recurrent restenosis rate was higher in 40 diffuse ISR lesions than that in 96 focal ISR lesions: 45% vs 18%, P75% was also the risk factor of recurrent restenosis Conclusion For the most patients with ISR, repeat PTCA or intracoronary stenting seems to be an effective and safe method The overall restenosis rate after repeat intervention for ISR is the same as that of initial intracoronary stenting
