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 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.
High performance liquid chromatography (HPLC) is currently the mainstream technology for detecting hemoglobin. Glycated hemoglobin (HbA1c) is a gold indicator for diagnosing diabetes, however, the accuracy of HbA1c test is affected by thalassemia factor hemoglobin F (HbF)/hemoglobin A2 (HbA2) and variant hemoglobin during HPLC analysis. In this study, a new anti-interference hemoglobin analysis system of HPLC is proposed. In this system, the high-pressure three-gradient elution method was improved, and the particle size and sieve plate aperture in the high-pressure chromatography column and the structure of the double-plunger reciprocating series high-pressure pump were optimized. The system could diagnose both HbA1c and thalassemia factor HbF/HbA2 and variant hemoglobin, and the performance of the system was anti-interference and stable. It is expected to achieve industrialization. In this study, the HbA1c and thalassemia factor HbF/HbA2 detection performance was compared between this system and the world’s first-line brand products such as Tosoh G8, Bio-Rad Ⅶ and D10 glycosylated hemoglobin analysis system. The results showed that the linear correlation between this system and the world-class system was good. The system is the first domestic hemoglobin analysis system by HPLC for screening of HbA1c and thalassemia factor HbF/HbA2 rapidly and accurately.
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.
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.
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.
Objective To establish a method for quality control of Astragalus Radix and Scutellariae Radix in Biqiaotong granules and provide basis for the establishment of quality standard. Methods The single-factor test method was used to investigate the factors of thin layer chromatography (TLC) conditions, including different extract method and solvents, developing system, comogemc agents, temperature, humidity, drawing amounts and thin layer boards, and to screen the best TLC conditions of Astragalus Radix and Scutellariae Radix . Results The TLC conditions of Astragalus Radix were used trichloromethane-methanel-water (13:7:2) as developing solvent, separated on silica gel G, heatd under 105℃ until the spots bacame clear. The TLC conditions of Scutellariae Radix were used methylbenzene-ethy acetate- formic acid-methanel (9:3:2:2) as developing solvent, separated on silica gel G, observed after 30 minutes under daylight until the spots were clear. Conclusions The spot features are clear, and with good separating degree, strong specificity, and good repeatability without the inference of negative control. The TLC method is simple, sensitive and accurate, which can be adopted for the quality control of Biqiaotong granules.
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 understand the nutritional status of vitamin D in some children aged 0-14 in Mianyang during the past 3 years and the changes of vitamin D nutritional status under home protection during the coronavirus disease 2019 (COVID-19) epidemic, so as to provide a theoretical basis for the monitoring and reasonable supplementation of vitamin D in children in this area after the epidemic.MethodsThe clinical data of children aged 0-14 who underwent physical examination in the Children’s Health Department of Mianyang Central Hospital from January to April 2018, from January to April 2019 and from January to April 2020 were analyzed retrospectively. High performance liquid chromatography tandem mass spectrometry was used to detect vitamin D, including vitamin D2, vitamin D3 and 25-hydroxyvitamin D [25(OH)D] in children’s serum. The differences in vitamin D components and 25(OH)D between different genders, different age groups, and different years were analyzed.ResultsA total of 12 348 children were included. The average vitamin D2 was (4.89±6.02) ng/mL, the average vitamin D3 was (22.91±9.29) ng/mL, the average 25(OH)D was (27.81±10.53) ng/mL, and 9 434 cases had sufficient 25(OH)D. The differences in vitamin D2, vitamin D3, 25(OH)D and 25(OH)D nutritional status in 2018, vitamin D2 and 25(OH)D in 2019, and vitamin D2 in 2020 between different genders were not statistically significant (P>0.05). There were statistically significant differences in vitamin D3 and 25(OH)D nutritional status in 2019, vitamin D3, 25(OH)D and 25(OH)D nutritional status in 2020 between different genders (P<0.05). From 2018 to 2020, vitamin D2 was the highest in infant group (P<0.05), while vitamin D3, 25(OH)D and 25(OH)D nutritional status were the highest in children group (P<0.05); vitamin D2 (χ2=143.106, P<0.001) showed an overall downward trend, vitamin D3 (F=400.178, P<0.001) and 25(OH)D (F=447.384, P<0.001) showed an overall upward trend; 25(OH)D nutritional status (χ2=103.566, P<0.001) was the highest in 2019.ConclusionsThe overall vitamin D nutritional status of children in Mianyang area is acceptable. Under the home protection, the average level of children’s serum 25(OH)D has little change, while the nutritional status of 25(OH)D has decreased significantly. After the outbreak of COVID-19, more attention should be paid to the monitoring and supplementation of vitamin D in school-age female children.
ObjectiveTo investigate the diagnostic value of lateral chromatography for cryptococcal capsular polysaccharide antigen in cryptococcal infection.MethodsThe data of patients who detected cryptococcal capsular polysaccharide antigen in West China Hospital of Sichuan University in 2018 were collected. The sensitivity, specificity, positive predictive value and negative predictive value of cryptococcal capsular polysaccharide antigen detected by lateral chromatography were analyzed. The samples with positive lateral chromatography and definite clinical diagnosis were compared with the results of ink staining and fungal culture.ResultsA total of 721 cases were detected. The sensitivity, specificity, positive predictive value and negative predictive value of lateral chromatography detection were 100.00%, 99.39%, 93.93%, 100.00%, respectively. The positive rates of ink staining, fungal culture and cryptococcal capsular polysaccharide antigen for cryptococcal infection were 63.46%, 48.00% and 100.00%, respectively. Sixty-two patients were clinically diagnosed, including 45 cases of cryptococcal meningitis (72.58%), 16 cases of cryptococcal pneumonia (25.81%), and 1 case of bone cryptococcal infection (1.61%).ConclusionsLateral chromatography detection for cryptococcal capsular polysaccharide antigen shows well performing sensitivity and specificity in the diagnosis of cryptococcal infection. Considering its rapid and simple pre-operation, cryptococcal capsular polysaccharide antigen detection with lateral chromatography has good application value for early diagosis of cryptococcal infection.