Objective To observe the inhibitory effect of the extracts of Nidus Collocaliae on avian influenza A H5N1 virus in vitro. Methods Nidus Collocaliae water extract, artificial gastric juice digestion products of Nidus Collocaliae water extract, and artifitial intestinal juice digestion products of Nidus Collocaliae water extract were prepared for the experimental study. 293T cells transfection in vitro was carried out. The effects of 3 kinds of Nidus Collocaliae extracts on H5N1 pseudovirus and VSV-G pseudovirus were determined by luciferase detection kit. Blood clotting response to erythrocyte hemagglutinin subtypes H5, H7, H9 antigens and the inhibitory effects of 3 kinds of Nidus Collocaliae extracts were observed. The effects of 3 kinds of Nidus Collocaliae extracts on neuraminidase activity were determined by neuraminidase inhibitor screen kit. Results The 3 kinds of Nidus Collocaliae extracts had inhibitory effects on H5N1 avian influenza pseudovirus, the effects being enhanced with the increase of the concentrations of Nidus Collocaliae extracts. Of the 3 extracts, artificial intestinal digestion products had the strongest inhibitory effect, while Nidus Collocaliae water extract had the weakest effect. However, Nidus Collocaliae extracts had no obvious effect on VSV-G pseudovirus. The concentration of H5, H7 antigen for positive blood clotting response was 1 ∶ 128, and that of H9 antigen was 1 ∶ 256. The 3 kinds of Nidus Collocaliae extracts at certain concentrations could inhibit blood clotting response to H5, H7, H9 antigen, but had no obvious effect on neuraminidase. Conclusion The anti-H5N1 virus effect of Nidus Collocaliae extracts has been achieved probably through resisting hemagglutinin.

Protein polypeptides are a class of bioactive substances that play a crucial role in maintaining the stability of various functions of the organism.Rapid and accurate detection of their levels could help in the diagnosis of diseases,the monitoring of drug therapy and the research and development of medicines,which is of great significance in the fields of clinical medicine,biology and pharmacy.Conventional protein polypeptides detection methods,such as Western blotting and enzyme-linked immunosorbent assay,still have problems like low sensitivity or difficulty in determining more than 1 analyte simultaneously.Liquid chromatography-mass spectrometry(LC-MS)has the advantages of specificity,sensitivity and high throughput.However,low ionization efficiency of macromolecules and strong biological matrix effects limit the feasibility of direct detection of protein polypeptides by LC-MS,which has led to the development of signal conversion and amplification strategies based on LC-MS technology.In this review,we summarized the research progress of sample pretreatment methods and signal conversion and amplification strategies for quantification of protein polypeptides in vivo based on LC-MS in recent years,providing a reference for developing specific high-sensitivity detection methods for low-abundance protein polypeptides in complex samples based on LC-MS technology.