ObjectiveTo investigate the methodology of a newly developed highpressure liquid chromatography electrochemical system in urinary 8hydroxydeoxyguanosine (8OHdG) quantification. MethodsQuantification of urinary 8OHdG with ESA 5600 Coularray system among 21 children from liver cancer highrisk areas, Fusui country, in contrast with 63 controls from Nanning city, Guangxi province.ResultsThe resolution, sensitivity, linearity, precision and recovery of this approach all fully meet the requirement of routine urinary 8OHdG quantification. The mean 8OHdG level of this population was (5.26±0.41) ng/mg creatinine, higher than previous report 〔(4.62±0.091) ng/mg creatinine〕 by similar method.ConclusionWith cautious design and modification, this method is reliable and accurate in high throughput quantification of urinary 8OHdG.
OBJECTIVE: To purify and study Schwann cells cytoplasmic neurotrophic protein. METHODS: The dissociated SC taken from 300 newborn rats sciatic nerves were cultured, collected, ultrasonicated and ultraspeed centrifuged. The supernates were ultrafiltrated and concentrated by using ultrafiltration units with PM10, PM30, PM50 ultrafiltration membranes. The ultrafiltrated-concentrated solution with the protein molecular weight 10-30 ku, 30-50 ku and gt; 50 ku were collected respectively. The dissociated spinal cord motoneurons of 14 days embryonic rats were cultured with serum-free conditional medium and the additional SC cytoplasmic proteins were added into the medium. The results showed that the 10-30 ku and gt; 50 ku SC cytoplasmic proteins were able to maintain the survival of motoneurons for 24 hours. Then the 26 ku and 58 ku proteins were further extracted and purified from SC cytoplasm by high pressure liquid chromatography, and their neurobiological activities were studied. RESULTS: The 26 ku and 58 ku Schwann cell’s cytoplasmic proteins were able to maintain the survival of motoneurons cultured in the serum-free medium for 48 hours. The highest biological activity concentration is 20 ng per well. CONCLUSION: Schwann cells cytoplasm contains motoneuron neurotrophic proteins with molecular weight 26 ku and 58 ku.
Objective To determine the best threshold value of hemoglobin A2 (HbA2) for diagnosis of β-thalassemia (β-thal) carriers by using high performance liquid chromatography (HPLC), and to improve the application value of HbA2 as a diagnostic index for β-thal carriers to reduce the rates of missed diagnosis and misdiagnosis. Methods Using reverse dot blot (RDB) as a gold standard method, HbA2 results of 1 007 β-thal carriers and 606 normal controls in the past two years determined by HPLC were divided into true positive, false positive, true negative, and false negative based on the different threshold values of HbA2 results. Then, the evaluation indexes such as sensitivity, specificity, positive and negative likelihood ratio, and Youden’s index were evaluated. Next, the receiver operator characteristic (ROC) curve was drawn to determine the best threshold value of HbA2 for diagnosis of β-thal carriers by HPLC. Results If ≥4.0% was taken as the threshold value of HbA2 for diagnosis of β-thal carriers by HPLC, the evaluation indexes values were shown as follows: sensitivity 99.21%, specificity 99.34%, positive likelihood ratio 150.30, negative likelihood ratio 0.008, and Youden’s index 0.99. The Youden’s index was better than the other threshold values, and the corresponding tangent point was the peak point of the ROC curve. Conclusion When ≥4.0% serves as the best threshold value of HbA2 for diagnosis of β-thal carriers using HPLC, integrated evaluation performance of the corresponding sensitivity and specificity is the most ideal, and the authenticity of the diagnostic test is the best.
Objective To study the distribution and concentration of meropenem in rabbit bile. Methods The rabbits were cannulated with a silicone tube in the common bile duct and the blank bile was collected. The rabbits were then administered intravenously with meropenem. Multiple bile samples (1.5 ml) were collected at different phases after the administrations. According to requirement of the high performance liquid chromatography (HPLC), the specificity test was undertook. The blank bile was then mixed with meropenem and mobile phase, respectively, in order to obtain a series of bile samples at different concentrations ranging from 0.5 to 500 μg/ml. The samples were analyzed with HPLC and the chromatographic peak area of meropenem contents were quantitated through external reference method. The linear regression equation was used to analyzed the relationship between the drug concentrations and the chromatographic peak areas. The bile samples that were collected after drug administrations were pretreated and the chromatographic peak areas were assayed by the liquid chromatograph. The bile concentrations were then calculated according to the regression equation, and the concentration-time distribution of meropenem in the bile was obtained ultimately. Results The specificity test indicated the bile dopant peak and the meropenem chromatographic peak were well-separated under chromatographic condition of the mobile phase. The standard curve regression equation was S=2 209.10C-1 251.34, r=0.999 9, and minimum quantitation limit of meropenem was 0.5 μg/ml. After a single i.v. administration of 75 mg/kg of meropenem in each rabbit, drug concentrations reached (38.36±14.17) μg/ml immediately in bile， which significantly exceeded the minimum inhibitory concentrations (MIC90) for most gram negatives, which range from 0.031 to 2 μg/ml. The bile concentration of meropenem decreased quickly over time, and meropenem was eliminated completely in rabbit bile 3 hours after intravenous injection. Conclusion Meropenem could achieve adequate bile concentration for the treatment of biliary tract infection due to susceptible bacteria. However, because of its rapid biliary elimination, meropenem should be used in shorter interval time.
ObjectiveTo study the effects of different penetration enhancers on the transdermal penetration of Miao medicine named Diploclisia affinis. MethodsImproved Franz diffusion cell was adopted as the apparatus for in vitro mouse' skin permeation. The kinetic parameters of percutaneous absorption, such as penetration rate, enhancing rate (ER), and lag time (Tlag) were determined by high performance liquid chromatography. Azone, oleic acid (OA) and borneol were investigated for percutaneous absorption effects. ResultsThe penetration rates of the medicine with 3% azone, OA and borneol added were respectively (214.1872±13.5690), (227.5544±9.8490), and (168.1187±21.5640) μg/(cm2·h), and the ER was 1.61, 1.71, and 1.26 compared with the penetration rate of that with nothing added. The Tlag was 2.1081, 1.8256, and 2.9655 hours. ConclusionAll the penetration enhancers can increase significantly the absorption of Miao medicine named Diploclisia affinis, especially 3% OA is the best, but 3% borneol may make the Tlag longer.
ObjectiveTo determinate the concentration of isonicotinyl hydrazide (INH) in the hydrothorax and thereby increase the drug concentration of the hydrothorax to enhance the anti-tuberculosis efficacy through experiments. MethodsBetween February and June 2009, we used high performance liquid chromatography (HPLC) to determinate the concentration of INH in the hydrothorax of tuberculosis (TB) patients. The separation of sample was performed on Agilent ZORBAX SB-C18 (5 μm, 4.6 mm×2.5 mm) column with a fixed sample injection volume of 20 μL. The mobile phase was methanol-water (20︰80) at a flow rate of 1 mL/min. The ultraviolet detective wavelength was set at 254 nm; The column temperature was room temperature. ResultsIn the range of 0.25-10.00 μg/mL (r=0.998 9), moxi-floxacin showed a good linear relation in HPLC. The recoveries of moxi-floxacin at three concentrations (0.5, 5.0, and 10.0 μg/mL) were 97.95%, 100.64%, and 102.84%, respectively, with intra-day relative standard deviation (RSD) at 3.49%, 1.45%, and 2.03%, respectively and intra-day RSD at 3.85%, 5.68%, 4.15%, respectively. ConclusionThe measuring method adopted in the experiment can accurately determinate the concentration of INH in the hydrothorax with high sensitivity and exceptional reproducibility.
ObjectiveTo establish a method for content determination of ferulic acid in Piwang massage lotion. MethodsHigh performance liquid chromatography was used. The analysis was carried on Diamonsil C18 (150 mm×4.6 mm, 5 μm, Dimma Science and Technology Co. Ltd.) column with mobile phase consisted of methanol-2% acetic acid (32︰68). The column temperature was 30℃. The detection wavelength was 320 nm. ResultsThe responses of ferulic acid liner in range of 4.55-91.00 μg/mL (R2=0.999 9). The average recovery of ferulic acid was 98.78% (relative standard deviation is 2.668%). ConclusionThe method is simple, rapid and good repeatability. It can be used for quality control of Piwang massage lotion
ObjectiveTo study the pharmacokinetics of lovastatin/niacin sustained-release tablets in healthy Chinese volunteers. MethodsEligible subjects were enrolled to receive a single dose of 20/500, 20/750 and 20/1 000 mg lovastatin/niacin sustained-release tablets and multiple dose of 20/1 000 mg lovastatin/niacin sustainedrelease tablets, one time per day, sustained for 5 days, respectively. Blood samples were obtained before dosing and up to 10, 20, 30, and 45 minutes, and 1 hour, 1.5, 2, 2.5, 3, 3.5, 4, 5, 7, 9, 12, and 15 hours after dosing. Niacin, niacinamide, nicotinuric acid and lovastatin were detected by high performance liquid chromatography-tandem mass spectrometry method. ResultsThe peak concertration and the area under the plasma concentration-time curve (0-t) of nicotinuric acid had linear dynamics characteristics with the dosage when the dose of niacin was between 500 and 1 000 mg. After multiple dosing, pharmacokinetics parameters of nicotinuric acid and lovastatin were close. No significant diTherence was found between male and female subjects. ConclusionLovastatin/niacin sustained-release tablets possess linear kinetics. Accumulation is not significant after multiple dosing. Gender doesn't affect the pharmacokinetics parameters.
ObjectiveTo establish an accurate and sensitive high performance liquid chromatography-mass spectrometric (HPLC/MS/MS) method for determination of vorinostat (SHA) and M2 metabolites in human serum, which was applicable for pharmacokinetic study of SHA. MethodsThe essay was conducted with an API 3000 HPLC-MS/MS system consisted of a Gemini C18 column (50 mm×3 mm, 3 μm), and the mobile phase consisted of methanol-acetonitrile-water-1 mol/L NH3-formic acid (25:15:60:0.1:0.05) at a flow rate of 0.23 mL/min. Acidulated serum samples were extracted by 3.5 mL diethyl ether which contains 3% isopropyl alcohol and was operated under the multiple reaction monitoring mode using the electrospray ionization technique. d5-SHA was used as the internal standard. ResultsThe retention time of SHA, M2 metabolite and internal standard were 4.1, 3.1 and 4.0 minutes, respectively. The linear range of SHA and M2 metabolite were in the range of 1-1 000 and 2-2 000 ng/mL, and the limit of quantity were 1.0 and 2.0 ng/mL; the method recovery were 93.0%-99.3% and 88.11%-104.12%, respectively. Matrixes effect of SHA and M2 metabolite were blow 9.0%. ConclusionThis method for the quantitative determination of SHA and M2 in human serum was proved to be simple, rapid, sensitive and accurate; it can be applied in the determination of SHA and M2 metabolite.
ObjectiveTo explore the possible active mechanism of the basic fibroblast growth factor (bFGF) long circulation l iposome (LCL) (bFGF+LCL) on spinal cord traction injury in rats at the level of proteomics. MethodsTwenty Sprague Dawly rats were randomly divided into groups A and B, 10 rats in each group. The models of spinal cord traction injury was established at T12-L3 spines. The rats were not treated in group A, and the rats were treated with bFGF+LCL (20μg/ kg) in group B. At 3 weeks after operation, the rats were sacrificed for harvesting T13-L2 spinal tissue specimens. The protein was extracted and quantified in the spinal tissue firstly. The proteins from spinal tissue were separated by two-dimensional gel electrophoresis and identified by mass spectrometry. The different expression profiling was established in each group, and the differentially expressed protein was determined by comparing the level of each spot with gel imaging software and manually. The proteins were identified by nano ultra-high performance liquid chromatography-electrospray tandem mass spectrometry (NanoUPLC-ESI-MS/MS), and the proteins were classified. ResultsThe differentially expressed protein spots were found in 2 groups. Compared with group A, 4 spots were up-regulated and 6 were down-regulated in group B. NanoUPLC-ESI-MS/MS results showed that 18 significant proteins were identified in 26 differentially expressed proteins, including 4 apoptosis-related proteins, 3 nerve signal transduction related proteins, 7 proteins involved in metabolism, 1 unknown function protein, and 3 unnamed proteins. ConclusionThe differentially expressed proteins are found in spinal cord traction injury of rats treated with bFGF+LCL. bFGF+LCL can affect the proteins expression in rats with spinal cord traction injury. The possible active mechanism is that it has protective and repair effects on injured spinal cord by nerve signal transduction, and regulation of nerve cells apoptosis and metabolism.