Adenosine triphosphate promotes locomotor recovery after spinal cord injury by activating mammalian target of rapamycin pathway in rats

The mammalian target of rapamycin （mTOR） pathway plays an important role in neuronal growth, proliferation and differentiation. To better understand the role of mTOR pathway involved in the induction of spinal cord injury, rat models of spinal cord injury were established by modified Allen＇s stall method and interfered for 7 days by intraperitoneal administration of mTOR activator adenosine triphosphate and mTOR kinase inhibitor rapamycin. At 1-4 weeks after spinal cord injury induction, the Basso, Beattie and Bresnahan locomotor rating scale was used to evaluate rat locomotor function, and immunohistochemical staining and western blot analysis were used to detect the expression of nestin （neural stem cell marker）, neuronal nuclei （neuronal marker）, neuron specific enolase, neurofilament protein 200 （axonal marker）, glial fibrillary acidic protein （astrocyte marker）, Akt, mTOR and signal transduction and activator of transcription 3 （STAT3）. Results showed that adenosine triphosphate-mediated Akt/mTOR/STAT3 pathway increased endogenous neural stem cells, induced neurogenesis and axonal growth, inhibited excessive astrogliosis and improved the locomotor function of rats with spinal cord injury.

A useful quantitative model for determination of enantiomeric composition of racemate praziquantel by ultraviolet spectroscopy combined with partial least squares and its application to praziquantel tablets

A simple and novel method has been proposed to determine the enantiomeric composition ofracemate praziquantel(PzQ)by using the analysis of ultraviolet(UV)spectroscopy combinedwith partial least squares(PLS),This method does not rely on the use of expensive carbohydratessuch as cyclodextrins,but on the use of inexpensive sucrose,which is equally effective as car-bohydrate.PZQ has two enantiomers.Through measuring the slight diference in the UV spectralabsorption of PzQ due to different interactions between its two enantiomers and sucrose,theenantiomeric composition was determined by a quantitative model based on PLS analysis.Themodel showed that the correlation coeficients of calibration set and validation set were 0.9971and 0.9972,respectively.The root mean square error of calibration(RMSEC)and the root meansquare error of prediction(RMSEP)were 0.0167 and 0.0129,respectively,Then,the independentdata of PZQ tablets were also used to test how well the quantitative model of PLS predicted theenantiomeric composition,The ratio of S-PZQ in tablet was 0.492,determined by high-perfor-mance liquid chromatography as the reference value,Six solutions of the tablet samples were prepared,and the ratios of S-PZQ in tablet samples in the validation set were predicted by the PLS model.,Theirrelative erors with the reference value were not more than 4%.Therefore,the established model couldbe accurate and employed to predict the enantiomeric compositions of PzQ tablets.