This study was aimed to establish an effective method for the simultaneous content determination of strychnine and brucine in rat plasma.The Wistar rat plasma samples were processed by liquid-liquid extraction and separated on a UPLC BEH C18 column.The mobile phase was acetonitrile - acid water (17?83).The acid water was 0.02 mol·L-1.The potassium dihydrogen phosphate and 0.014 8 mol·L-1 sodium heptane sulfonate was mixed with equal amount.The 10% phosphonic acid was used to adjust the system to the pH of 2.8.The detection wavelength was set at 260 nm.The results showed that foreign materials in the Wistar rat plasma did not interfere with the content determination of samples.The calibration curve of strychnine was in good linearity within the range of 0.067 84-3.392 00μg·mL-1.The calibration curve of brucine was in good linearity with the range of 0.052 48-2.624 00μg·mL-1.The intra-and inter-day precisions were less than 10%.The mean extraction recoveries were more than 85%.The stability results met the requirements for biopharmaceutical analysis.It was concluded that the UPLC detection method was sensitive and precise,which can be used in the pharmacokinetics study of strychnine and brucine in Tong-Mai(TM) pill.

We wished to ascertain the prevalence as well as the genetic and antigenic variation of infectious bronchitis viruses (IBVs) circulating in the Guangxi Province of China in recent years. The S1 gene of 15 IBV field isolates during 2012-2013 underwent analyses in terms of the similarity of amino-acid sequences, creation of phylogenetic trees, recombination, and serologic identification. Similarities in amino-acid sequences among the 15 isolates of the S1 gene were 54.3%-99.6%, and 43.3%-99.3% among 15 isolates and reference strains. Compared with the vaccine strain H120, except for GX-YL130025, the other 14 isolates showed a lower similarity of amino-acid sequences of the S1 gene (65.1-81.4%). Phylogenetic analyses of the S1 gene suggested that 15 IBV isolates were classified into eight genotypes, with the predominant genotype being new-type II. Recombination analyses demonstrated that the S1 gene of the GX-NN130048 isolate originated from recombination events between vaccine strain 4/91 and a LX4-like isolate. Serotyping results suggested that seven serotypes prevailed during 2012-2013 in Guangxi Province, and that only one isolate was consistent with the vaccine strain H120 in serotype (which has been used widely in recent years). The serotype of recombinant isolate GX-NN130048 was different from those of its parent strains. These results suggested that not only the genotype, but also the serotype of IBV field isolates in Guangxi Province had distinct variations, and that increasing numbers of genotypes and serotypes are in circulation. We showed that recombination events can lead to the emergence of new serotypes. Our study provides new evidence for understanding of the molecular mechanisms of IBV variations, and the development of new vaccines against IBVs.
Animals ; Antibodies, Viral ; blood ; Chickens ; China ; Coronavirus Infections ; blood ; veterinary ; virology ; Genetic Variation ; Genotype ; Infectious bronchitis virus ; classification ; genetics ; immunology ; isolation & purification ; Molecular Sequence Data ; Phylogeny ; Poultry Diseases ; blood ; virology ; Sequence Homology, Amino Acid ; Spike Glycoprotein, Coronavirus ; chemistry ; genetics ; immunology