Objective:To construct the prokaryotic expression vector of Coxsackievirus A16(CA16)viral protein 1(Vp1),express it in Escherichia coli(E.coli)BL21,purify the protein,prepare rabbit polyclonal antibodies,and identify the immunoreactivity of the antibodies.Methods:Bioinformatics online tools were used to predict the amino acid composition,conserved domains,secondary and tertiary structures of the Vp1 protein.The Vp1 gene of CA16 was amplified and cloned into the prokaryotic expression vector pET28a(+).The pET28a-Vp1 was transformed into E.coli BL21,and the expression was induced using isopropyl β-D-thiogalactopyranoside(IPTG).Western blotting method was used to identify the induced expression of Vp1 protein,and the induction time and temperature were optimized to improve the expression efficiency.Two female SPF New Zealand white rabbits were taken,and the purified recombinant protein Vp1 was used to immunize the rabbits to prepare rabbit anti-Vp1 protein polyclonal antibodies.The antibody titer was determined by ELISA method,and the immunoreactivity of the antibodies was identified by Western blotting method.Results:The bioinformatics analysis results showed that the Vp1 gene encoded 297 amino acids,with a relative molecular mass of 33 046.39 and an isoelectric point of 8.32,belonging to a hydrophilic protein;in the secondary structure,α-helix accounted for 15.15％,random coil accounted for 67.68％,and extended strand accounted for 17.17％.Sequencing of the recombinant plasmid pET28a-Vp1 confirmed that the pET28a-Vp1 plasmid was correctly constructed.The Western blotting results showed that the target protein was expressed in the IPTG induction group at a relative molecular mass of 33 000,and the target protein was mainly expressed in inclusion bodies.The optimal induction conditions for protein expression were IPTG concentration of 0.4 mmol·L-1,temperature of 16℃,and induction time of 20 h.The ELISA assay results showed that the titer of the rabbit polyclonal antibody was 1:1 024 000.The Western blotting results showed that the Vp1 rabbit polyclonal antibody could bind to the viral Vp1 protein in the CA16-infected cells.Conclusion:The polyclonal antibody against CA16 Vp1 is successfully prepared,and this antibody has significant binding characteristics to CA16 Vp1,which can be used for the diagnosis of enterovirus infection and the development of treatment methods.

Chronic cough can occur in children of all ages, and the incidence rate and consultation rate increase each year.Clarifying the cause of chronic cough is the key to treatment.At present, there are no convenient, operable and unified standards for etiological analysis of chronic cough in the world.Therefore, the etiological analysis of chronic cough has always been a hot topic in clinical research.With the development of diagnosis and treatment technology, the role of pulmonary function and exhaled nitric oxide in the diagnosis of chronic cough has attracted attention.This article reviews the application value of pulmonary function combined with exhaled nitric oxide in etiology analysis of chronic cough in children, to provide reference for etiology analysis of chronic cough in children.

Novel coronavirus (2019-nCoV) is the pathogen of COVID-19. Some severe cases may suffer from respiratory failure or even death, which poses a great challenge to global public health. 2019-nCoV proteins not only participate in virus proliferation, but also play an important role in antagonizing host innate immune response, especially interferon response. In this paper, 2019-nCoV proteins involved in regulating host interferon response and the complex interaction between 2019-nCoV and interferons were summarized, aiming to provide a theoretical reference for the prevention and control of COVID-19.

Objective: To investigate the relationship between P27，P53 and PCNA expression in human gastric carcinoma tissues and clinicopathological parameters. Methods: The expression of P27，P53 and PCNA in 62 human gastric carcinoma tissues was examined with immunohistochemistry SP method. Results: Positive rates of P27，P53 and PCNA expression were 37.1％, 40.4%，83.9％. P27 expression was related with Bormann type, infiltrative depth, lymph node and distant metastasis and clinical stage. P53 expression was related with sex of patients, distant metastasis and clinical stage. PCNA expression was related with age of patients and infiltrative depth of tumor. P27 positive expression group was higher than negative group as to 5-year survival. P27 expression was in reverse relation with PCNA expression. Conclusion: The expression of P27, P53 and PCNA may be regarded as an important marker in judging malignant degree of gastric carcinoma,distant metastasis and prognosis.

Objective To inquire into the relationship between infections of Toxoplasma gondii and apoptosis of spermatogenic cells. Methods Apoptotic spermatogenic cells of mice infected with Toxoplasma gondii were examined by Wright-Giemsa staining and terminal deoxynucleotidyl trans-Icrase (TdT) mediated deoxyuridine triphosphate (dUTP)-biotin nick-end labeling (TUNED techniques. Results Apoptosis rate of infective group of Toxoplasma was significantly higher than thai oi control group (F