Objective: To establish a GC method for the determination of content and content uniformity of memantine hydrochloride dispersible tablets.Methods: The sample was dissolved in water, alkalified by sodium hydroxide solution and extracted by methylene chloride.An HP-5 gas chromatography column (50 m×0.32 mm, 1.05 μm) was used.The column temperature was programming increased, and the initial temperature maintained at 120 ℃ for 3 min, and then raised to 220 ℃ at a rate of 10℃·min-1 and maintained for 7 min.A hydrogen flame ionization detector (FID) was used and the split ratio was 1∶1.The inlet temperature was 230 ℃ and the detector temperature was 260 ℃.The injection volume was 1 μl and the carrier gas was nitrogen with high purity at a flow rate of 3.0 ml·min-1.Adamantane was used as the internal standard, and the internal standard method was used for the calculation.Results: The calibration curve was linear over the range of 0.05-1.0 mg·ml -1 (r=0.999 7).The detection limit and the limit of quantification was 1.1 ng and 3.3 ng, respectively.The average recovery was 100.2% (RSD =0.73%, n=9).Conclusion: The method has the advantages of simple operation, small extraction process toxicity, little environmental pollution, high accuracy and high specificity, and can be used for the determination of content and content uniformity of memantine hydrochloride dispersible tablets.

OBJECTIVE:To establish the purity determination of bisacodyl by differential scanning calorimetry(DSC)and the valuation of uncertainty. METHODS:DSC was conducted to detect the purity of bisacodyl and determine the optimal testing condi-tions. According to related standards,indium enthalpy change values,measurement repeatability,weighing process,instrument tem-perature deviation and system software deviation were systematically analyzed. The results were verified by HPLC. RESULTS:When the fiducial probability P was 0.95,the standard value and uncertainty of content of bisacodyl was (99.88 ± 0.06)% mea-sured by DSC. Weighing process,instrument temperature deviation and system software deviation had great effects on the total un-certainty. The result of HPLC and DSC were the same. CONCLUSIONS:The established DSC can quickly and accurately determine the chemical purity of bisacodyl. The uncertainty evaluation is reliable. Regularly calibrated and verificated equipment and strict con-trol of the weighing process will help to improve the accuracy measured by DSC;and it provides a new analysis method for the de-termination of purity of bisacodyl.

OBJECTIVE:To establish a method for simultaneous residual determination of dichloromethane and ethyl acetate in bisacodyl raw material. METHODS:Head-space GC was performed on the capillary column of 6% cyanopropyl phenyl-94% di-methyl polysiloxane(DB-624)by temperature programming,the temperature of injector was 220 ℃,detector was flame ionization detector with temperature of 250 ℃,carrier gas was high purity nitrogen with the flow rate of 3.0 ml/min,split ration was 1∶10, headspace heating temperature was 70 ℃,equilibration time was 30 min,volume of headspace vial was 5 ml,and the injection volume was 1 ml. RESULTS:The linear range was 6-120μg/ml for dichloromethane(r=0.999 9)and 50-1 000μg/ml for ethyl ac-etate(r=0.999 9);the limit of quantitation was 0.2,1.7 μg,limit of detection was 0.06,0.5 μg;RSDs of precision,stability and reproducibility tests were no higher than 3%;recoveries were 100.30%-102.00%(RSD=0.63%,n=9) and 100.10 %-101.30%(RSD=0.44%,n=9). CONCLUSIONS:The method is simple and accurate,and can be used for the simultaneous residual deter-mination of dichloromethane and ethyl acetate in bisacodyl raw material.

OBJECTIVE:To investigate the similarity of dissolution curves between generic preparations and reference prepara-tions of Bisacodyl enteric-coated tablets in various dissolution mediums,and to provide reference for improving production technolo-gy and internal quality of generic preparations. METHODS:Paddle method was adopted with rotation speed of 75 r/min. The disso-lution test was performed using 1000 mL pH 6.0 phosphate buffer solution,pH 6.8 phosphate buffer solution,water containing 2% sodium lauryl sulfate. HPLC method was used to determine average accumulative dissolution of main components from 3 kinds of generic preparations and reference preparations at different time points to draw out dissolution curves. Similarity factor(f2)meth-od was used to the similarity of dissolution curves. RESULTS:Dissolution curves of reference preparations were basically the same in 3 kinds of dissolution mediums. But the dissolution curve f2 of one generic preparation among 3 manufactures to dissolution curve of reference preparation were ≥50,namely the similarity. CONCLUSIONS:The quality of generic Bisacodyl enteric-coat-ed tablets produced by different manufacturers is obviously different;the generic preparations needs to be further improved in the production technology and internal quality. For domestic generic preparation,it is necessary to strengthen the real-time monitoring of its dissolution curve,to ensure the drug quality.

Objective:To evaluate the measurement uncertainty in the determination of sodium valproate tablets by GC with an in -ternal standard method , and determine the main sources of uncertainty .Methods:A GC internal standard method was selected to sys-tematically analyze the uncertainty in the determination of sodium valproate tablets , including the sample quantity , dilution ratio, purity and area repeatability of chromatographic peaks .Results: The expanded uncertainty of sodium valproate tablets was 2.7%, and the determination range of sodium valproate tablets was (96.3 ±2.7)%(k=2).Conclusion:The established GC internal standard meth-od for the uncertainty evaluation is reliable , which is helpful to improving the quality evaluation and control of sodium valproate tablets .

Objective:To collect the clinical materials of primary liver cancer patients treated by gamma knife and analyze the treatment methods as well as short-term efficacy,and to provide a reference for the clinical treatment of primary liver cancer patients.Methods:A total of 633 patients with inoperable primary liver cancer were treated by body gamma knife.According to the TNM staging method of Union for International Cancer Control(UICC), there were 351 cases with clear TNM staging.Among them, there were 251 cases (71.5%) at T3 stage and 57 cases(16.2%) at T4 stage.The prescription dose of 200-600 cGy each time to the 40%-85% dose line covering the planned target volume(PTV), this program was performed 5 times per week, and the number of treatment ranged from 2 to 13.The biochemical and imaging changes were observed 2-3 months after treatment to evaluate the short-term efficacy.Results:During the treatment, 229(36.2%)patients had adverse reactions,100 (15.8%) patients appeared the reduced white blood cells, and 137 (21.6%) patients appeared the reduced platelets.On discharge from the hospital, 601 patients were improved, 22 patients had no obvious change, 5 cases were worse, and 5 cases died.The proportion of improved patients who received the cumulative dose between 3 000 cGy to 4 000 cGy was higher than those who received the cumulative dose less than 3 000 cGy(P<0.05).After treatment, the curative effects were evaluated in 45 patients during two and three months, including PR 77.8%(35/45) and SD 22.2%(10/45), and the total effective rate was 77.8%(35/45).No statistical differences in effective rates were found between different tumor diameter, single dose, and cumulative dose groups(P>0.05).Conclusion:The proportion of adverse reactions in the primary liver cancer patients treated with body gamma knife is relatively low and the short-term efficacy is ideal.Body gamma knife treatment is a safe and effective treatment method for the primary liver cancer patients.

Betatrophin is a newly found factor that affects the metabolisms of sugar and fat , which is mainly ex-pressed in the liver and adipose tissue .This factor not only has an influence on the glucolipid metabolism , but also has regulating effect on replicating pancreatic βcell.Glucose and lipid metabolic disorder and the decrease in the number of pancreatic βcell are main risk factors of diabetes , diabetic great vascular complications and other com-plications.Therefore, betatrophin level has close relationship with diabetes .

Objective:To study the valuation and uncertainty evaluation of the purity determination of aminopyrine by two different principle methods. Methods:According to Technical Norm of Primary Reference Material and Technical Norm of Measurement,HPLC and acid-base titration were selected for studying the valuation of the purity determination of aminopyrine, and the uncertainty evaluation of the two different principle methods was systematically evaluated. Results:By using the two different principle methods,the standard value and uncertainty of aminopyrine content was 99.66% ± 0.08%(k = 2,P = 0.95). Conclusion:The valuation and uncertainty evaluation of the purity determination of aminopyrine by using HPLC and acid-base titration are accurate and reliable,which can avoid the defects by using single analysis method,and is helpful to improve the level of quality evaluation and control of aminopyrine. The study provides scientific basis for the development of aminopyrine purity reference materials.

OBJECTIVE: To explore the interaction between BCL2-associated athanogene 5 (BAG5) and Parkin protein,and the regulatory mechanism of BAG5 protein on the level of Parkin protein. METHODS: We performed GST pull-down assay to identify which domain of PINK1 interacted with Parkin, and generated different deletions of BAG5 to identify the domains. Chase time experiment was done to determine the effect of co-regulation of BAG5 protein on the ubiquitination. We further examined the possible interaction between Parkin and PINK1 in 293A cells by co-immunoprecipitation method. RESULTS: BAG5 directly interacted with the Parkin, and all the 4 BAG domains interacted with the Parkin. BAG5 stabilized the Parkin by interfering its degradation via the ubiquitin-mediated proteasomal pathway. CONCLUSION BAG5 directly interacts with the Parkin, and BAG5 stabilizes the Parkin via the ubiquitin-mediated proteasomal pathway.
Adaptor Proteins, Signal Transducing ; metabolism ; Humans ; Parkinson Disease ; metabolism ; Protein Binding ; Ubiquitin-Protein Ligases ; metabolism ; Ubiquitination