Development of a predictive in vitro dissolution for clarithromycin granular suspension based on in vitro-in vivo correlations

The objective of this study was to evaluate the in vitro behavior of different clarithromycin granular suspensions based on a developed in vitro-in vivo correlation model, using one reference and two test formulations. In vitro release rate data were obtained for each product using the USP apparatus II, operated at 50?rpm under different pH conditions. The dissolution efficiency was used to analyze the dissolution data. In vivo study was performed on six healthy male volunteers under fasting condition. Correlation was made between in vitro release and in vivo absorption. A linear model was developed using percent absorbed data versus percent dissolved data from the three products. Dissolution condition of 0.1N HCl for 1?h and then phosphate buffer at pH 6.8 was found to be the most discriminating dissolution method. Rate of absorption for the reference as estimated by Wagner-Nelson deconvolution was correlated with in vitro release with a correlation coefficient of 0.99. The in vivo results for the two test products were compared to the predicted values using the reference model with a correlation coefficient of 0.94. Furthermore, multiple level C correlations were obtained for some pharmacokinetic parameters with the corresponding in vitro kinetic parameters with correlation coefficients exceeding 0.90. Moreover, the interpretation of the in vitro and in vivo data with reference to formulations was discussed.     

The impact of baseline covariates on the efficiency of statistical analyses of crossover designs

We investigate the impact of baseline covariates on the efficiency of statistical analyses of crossover designs. For practical considerations, we contemplate two different baseline methods: study baselines and period‐dependent baselines. For each baseline method, we establish analytical upper bounds for the relative efficiency of a large class of crossover designs, the totally balanced designs, under a model with the baseline covariates as compared with the model without the baseline covariates. We present numerical details based on these bounds for assorted scenarios and reveal implications of these results. Copyright © 2012 John Wiley & Sons, Ltd.     

高校教育管理人员的作满意度调查

目的研究高校教育管理人员工作满意的现状及其影响因素。方法采用自编的教育管理人员工作满意度问卷对310名高校教育管理人员进行问卷调查。结果高校教育管理人员的工作满意度处于中等偏上水平,其中晋升发展的满意度最低(x珋=2.78),同事关系的满意度最高(x珋=3.91)。不同性别、年龄、职务、月收入水平的高校教育管理人员的工作满意度得分差异显著;工作满意度与工作效率具有显著的正相关(r=-0.362,P0.01),回归分析表明,在控制了人口统计变量之后,工作本身的满意度可以显著正向预测工作效率(β=0.353,P0.001)。结论高校教育管理人员对晋升发展的满意度偏低;性别、年龄、职务、月收入等显著影响高校教育管理人员的工作满意度;教育管理人员对教育管理工作本身的满意可以显著正向预测工作效率。     

Review of the Potential of the Ni/Cu Plating Technique for Crystalline Silicon Solar Cells

Developing a better method for the metallization of silicon solar cells is integral part of realizing superior efficiency. Currently, contact realization using screen printing is the leading technology in the silicon based photovoltaic industry, as it is simple and fast. However, the problem with metallization of this kind is that it has a lower aspect ratio and higher contact resistance, which limits solar cell efficiency. The mounting cost of silver pastes and decreasing silicon wafer thicknesses encourages silicon solar cell manufacturers to develop fresh metallization techniques involving a lower quantity of silver usage and not relying pressing process of screen printing. In recent times nickel/copper (Ni/Cu) based metal plating has emerged as a metallization method that may solve these issues. This paper offers a detailed review and understanding of a Ni/Cu based plating technique for silicon solar cells. The formation of a Ni seed layer by adopting various deposition techniques and a Cu conducting layer using a light induced plating (LIP) process are appraised. Unlike screen-printed metallization, a step involving patterning is crucial for opening the masking layer. Consequently, experimental procedures involving patterning methods are also explicated. Lastly, the issues of adhesion, back ground plating, process complexity and reliability for industrial applications are also addressed.     

Increased sleep fragmentation in experimental autoimmune encephalomyelitis

Sleep disturbance in patients with multiple sclerosis is prevalent and has multifactorial causes. In mice with experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis, we determined the dynamic changes of sleep architecture and the interactions between sleep changes and EAE symptoms. The changes of sleep patterns were mainly reflected by altered sleep stage distribution and increased sleep fragmentation. Increased waking and decreased non-rapid eye movement sleep occurred after EAE onset and persisted through the symptomatic phase. There also was increased sleep state transition, indicating a reduction of sleep cohesiveness. Furthermore, the extent of sleep fragmentation correlated with the severity of disease. This is the first study of sleep characteristics in EAE mice demarcating specific changes related to the autoimmune disorder without confounding factors such as psychosocial impact and treatment effects. The reduction of sleep efficiency and cohesiveness supports the notion that enhancing sleep might facilitate the recovery of mice from EAE, pertinent to the multimodality treatment of multiple sclerosis.     

Amelioration of Endotoxin-Induced Uveitis in Rabbit by Topical Administration of Tacrolimus Proglycosome Nano-Vesicles

This work was aimed to improve the efficacy of tacrolimus in the treatment of endotoxin-induced uveitis (EIU) using propylene glycol modified lipid vesicles termed as proglycosome nano-vesicles (PNVs). PNVs were prepared by modified film hydration method. Experimental uveitis in rabbit eye was induced by an intravitreal injection of 20 μL of the endotoxin solution containing 100 ng of lipopolysaccharide endotoxin. In vivo efficacy of PNVs was determined by studying clinical symptoms of uveitis using slit lamp examination and by quantitatively measuring levels of tumor necrosis factor-alpha, interleukin-6, leukocytes and total proteins in aqueous humor, 24 h after intravitreal injection of endotoxin. Comparison was made with healthy, untreated and tacrolimus solution treated eyes. PNVs developed were nano-sized, deformable and showed sustained release of tacrolimus over period of 12 h. In vivo results indicated statistically significant difference between the effects of PNVs in the treatment of EIU compared to tacrolimus. PNV treatment not only subsides clinical symptoms of uveitis but also prevented breakdown of blood aqueous barrier. Tacrolimus loaded PNVs are potential new topical treatment for uveitis.