Determination of oxytetracycline hydrochloride in milk and egg white samples using Ru(bipy)3 2+ -Ce(SO4 )2 chemiluminescence.

A novel, rapid and sensitive chemiluminescence (CL) method for the determination of oxytetracycline hydrochloride (OTCH) is described in this paper. The presented method was based on the fact that OTCH could immensely enhance the CL of the reaction of cerium sulfate and tris(2,2-bipyridyl) ruthenium (II) in acidic medium. Under optimal experimental conditions, CL intensity was favorably linear for OTCH in the range 5.0 × 10-7 to 5.0 × 10-5  g/ml, with a detection limit of 1.5 × 10-7  g/ml (S/N = 3). The relative standard detection was 4.76% for 5.0 × 10-6  g/ml (n = 11). This method was successfully applied to the analysis of OTCH in milk and egg white samples. According to the results of the kinetic curves for OTCH in the Ru(bipy)3 2+ -Ce(SO4 )2 CL system, together with CL and ultraviolet (UV)-visible spectra, the possible mechanism of the CL reaction is discussed briefly.

Simultaneous determination of four anthraquinones in rat plasma by HPLC-FLD method and its pharmacokinetic study / 中国中药杂志

This paper aims to develop a method for the determination of aloe-emodin, rhein, chrysophanol and physcion and study the pharmacokinetic properties of four anthraquinones in rat plasma after oral administration of gardenia and rhubarb decoction. The plasma concentrations at different time points of four anthraquinones were determined by HPLC-FLD method. Plasma samples were extracted with liquid-liquid extraction procedure. Plasma samples were separated on a C18 column (4.6 mm x 150 mm, 5 μm), using 0.2% acetic acid and methanol as mobile phase at a flow rate of 1.0 mL min(-1) with gradient elution. The excitation and emission wavelengths were set at 430, 525 nm, respectively. DAS 2.0 software was applied to calculate the pharmacokinetic parameters. The results showed four anthraquinones can be absorbed. The main parameters of aloe-emodin, rhein, chrysophanol and physcion were as follows: C(max) for aloe-emodin was (0.085 ± 0.058), (3.772 ± 1.152), (0.464 ± 0.267), (0.028 ± 0.008) mg x L(-1) respectively; t(max) for rhein was (1.042 ± 0.510), (0.805 ± 0.307), (1.167 ± 0.283), (0.616 ± 0.162) h respectively; t½ for chrysophanol was (3.557 ± 1.250), (6.879 ± 1.126), (5.196 ± 2.032), (4.337 ± 1.816) h; AUC(0-t) for physcion was (0.504 ± 0.130), (9.558 ± 1.106), (2.545 ± 1.554), (0.052 ± 0.018) mg x h x L(-1). This paper developed a selective, accurate and sensitive HPLC-FLD method for the simultaneous determination of four anthraquiones in rat plasma.

Proteomic analysis of Helicobacter pylori in human gastritis and gastric cancer / 中南大学学报(医学版)

OBJECTIVE@#To establish 2-dimensional electrophoresis (2-DE) maps of Helicobac-ter pylori in human gastritis, and gastric cancer, to identify the differentially expressed proteins,and to discuss the role of bacterial factor in pathogenesis.@*METHODS@#The total proteins of Helicobacter pylori in human gastritis and gastric cancer were separated by immobilized pH gradient-based 2-DE. The differentially expressed proteins were screened by PDQuest analysis software and identified by peptide mass fingerprint based on matrix-assisted laser desorption/ionization time of flight mass spectrometry, and searched on database.@*RESULTS@#A well-resolved and reproducible 2-DE pattern of Helicobacter pylori was obtained from patients with human gastritis and gastric cancer. Fourteen differentially expressed proteins were identified, including proteins related to anti-oxidation,molecular chape-rones and detoxification, enzymes related to metabolism,proteins related to cytoarchitecture,and proteins related to signal conduction.@*CONCLUSION@#A well-resolved and reproducible 2-DE pattern of Helicobacter pylori in human gastritis and gastric cancer is established and differentially expressed proteins from these 2 diseases are identified. The differentiation of protein expression may play an important role in the pathogenesis of gastric cancer.

Nested case-control study on the influence factors of perinatal stage transmission of hepatitis B virus / 中南大学学报(医学版)

OBJECTIVE@#To determine the influence factors of perinatal stage transmission of hepatitis B virus (HBV) and to provide scientific evidence for the prevention of perinatal stag transmission of HBV.@*METHODS@#A 1:1 matched nested case-control study was conducted, and 141 pair of pregnant women with HBsAg-positive and their newborns were enrolled. A questionnaire was performed and blood-related indicators were detected. The data were dealt with single factor analysis and conditional logistic regression analysis using SPSS 13.0 and SAS 8.1.@*RESULTS@#Single factor paired Chi-square test showed that education, first class family history, disfunction of liver, serum glutamic-pyruvic transaminase, systematic treatment, intrahepatic cholestasis of pregnancy (ICP), fetal distress, and vaccinating hepatitis B immune globulin (HBIG) were the risk factors of perinatal stage transmission of HBV. Conditional logistic regression analysis indicated that first class family history, vaccinating HBIG, systematic treatment, and ICP were the risk factors of perinatal stage transmission of HBV.@*CONCLUSION@#For women with HB-sAg-positive, active treatment, the standard vaccination of HBIG, and preventing and controlling the incidence of ICP may reduce the incidence of perinatal stage transmission of HBV.