Development of liposomal salbutamol sulfate dry powder inhaler formulation.

The purpose of our study was to develop a formulation of liposomal salbutamol sulfate (SBS) dry powder inhaler (DPI) for the treatment of asthma. Liposomes of high encapsulation efficiency (more than 80%) were prepared by a vesicular phospholipid gel (VPG) technique. SBS VPG liposomes were subjected to lyophilization using different kinds of cryoprotectants in various mass ratios. Coarse lactose (63-106 microm) in different mass ratios was used as a carrier. Magnesium stearate (0.5%) was added as a lubricator. The dry liposomal powders were then crushed by ball milling and sieved through a 400-mesh sieve to control the mean particle size at about 10 microm. The effects of different kinds of cryoprotectants and the amount of lactose carrier on the fine particle fraction (FPF) of SBS were investigated. The results showed that the developed formulation of liposomal dry powder inhaler was obtained using lactose as a cryoprotectant with a mass ratio of lyophilized powder to carrier lactose at 1 : 5; 0.5% magnesium stearate was used as a lubricator. The value of FPF for SBS was 41.51+/-2.22% for this formulation. Sustained release of SBS from the VPG liposomes was found in the in vitro release study. The study results offer the promising possibility of localized pulmonary liposomal SBS delivery in the anhydrous state.

[Three-dimensional design of surgery for mandibular retrusion].

OBJECTIVE: To explore the feasibility of surgical design for mandibular retrusion using three-dimensional software. METHODS: Three-dimensional reconstruction was performed by Mimics software based on the preoperative CT data. The model of the maxillofacial region was imported into Rapidform software for measuring the associated parameters and Geomagic software for simulation of osteotomy. The reliability of the virtual operation was validated during the surgery. RESULTS: The model of mandibular retrusion was reconstructed and successfully used to simulate the surgery. The simulation result was applied in subsequent actual surgery and good surgical outcomes were achieved. CONCLUSION: The three-dimensional software can be used to simulate the surgery for mandibular retrusion and improve the predictability and accuracy of the surgery.