Animal experiment on influenza virus infection carries certain biohazard risk, with a threat to the health of researchers and public health.The risk levels differ by influenza virus types and subtypes.This article combs the domestic and national laws and rules, and explores the biosafety management of animal study on influenza virus.

Preparation of maternal strain A/PR/8/34 HA antiserum for influenza virus classical reassortment. A/PR/8/34 virus was digested by bromelain after inactivation and purification. 5%-20% sucrose continuous density gradient centrifugation method was used to purify HA protein. SIRD method was used to select the target protein. SDS-PAGE method was used to identified HA protein. High Immunogenic A/PR/8/34 HA protein was successfully prepared and HI titer reached 10240. High purity HA antiserum was identified by SIRD method. The key reagent in the classical reassortment of influenza virus was prepared, and the complete set of technical methods were explored, which laid the foundation for the independent research and development of seasonal influenza vaccine strains of China.
Animals ; Antibodies, Viral ; immunology ; Electrophoresis, Polyacrylamide Gel ; Female ; Hemagglutination Inhibition Tests ; Hemagglutinin Glycoproteins, Influenza Virus ; analysis ; immunology ; Humans ; Influenza A Virus, H1N1 Subtype ; genetics ; immunology ; Influenza, Human ; immunology ; virology ; Rabbits ; Reassortant Viruses ; genetics ; immunology

Objective:To detect the changes of left ventricular myocardial work parameters, and evaluate the left ventricular systolic function in patients with hyperglycemia during pregnancy by left ventricular pressure-strain loop (PSL).Methods:From June 2021 to March 2022, 97 pregnant women who were admitted to the Second Affiliated Hospital of Harbin Medical University and clinically diagnosed as gestational hyperglycemia were prospectively and randomly selected. According to the blood glucose level, the patients were divided into gestational dominant diabetes mellitus (ODM) group(39 cases) and gestational diabetes mellitus (GDM) group(58 cases). Meanwhile, another 62 healthy pregnant women were selected as control group. The basic clinical data of the pregnant women were collected, and the conventional two-dimensional parameters of the heart were collected. The global longitudinal strain (GLS) was analyzed by two-dimensional speckle tracking technique. Then the cuff blood pressure was used as the left ventricular pressure to construct a non-invasive left ventricular pressure-strain loop. The global myocardial work index (GWI), global constructive work (GCW), global wasted work (GWW) and global work efficiency (GWE) of each group were calculated and compared. The correlation between myocardial performance parameters and GLS, glycated hemoglobin(HbA 1c) were analyzed, and the independent factors affecting left ventricular systolic function were obtained by Logistic regression analysis. Twenty cases were randomly selected from the study subjects, and the intraclass correlation coefficients(ICC) of within the observers and between observers were calculated for repeatability test. Results:①Conventional ultrasound parameters: There were no significant differences among the three groups (all P>0.05). ②GLS and left ventricular myocardial performance parameters: GWI, GWE, GCW and GLS in GDM and ODM groups were significantly lower than those in control group (all P<0.001), GWW was significantly higher than control group ( P<0.001); GWI, GWE, GCW and GLS in ODM group were lower than those in GDM group (all P<0.001), while GWW was higher than control group ( P<0.001). ③GWE, GWI and GCW were negatively correlated with GLS ( r=-0.525, -0.408, -0.435; all P<0.05), GWW was positively correlated with GLS ( r=0.348, P<0.05). GWE, GWI and GCW were negatively correlated with HbA 1c ( r=-0.325, -0.262, -0.250; all P<0.05), while GWW was positively correlated with HbA 1c ( r=0.175, P<0.05). ④GWE, 1 h oral glucose tolerance test and HbA 1c were the influencing factors of left ventricular systolic function in patients with hyperglycemia during pregnancy. ⑤The predictive values of GWI, GWE, GCW, GWW and GLS for cardiac function in patients with gestational hyperglycemia were high, and the predictive value of GWE was the highest (AUC: 0.87, the best truncation value: 94.5%, specificity: 0.76, sensitivity: 0.82) and better than GLS. ⑥The repeatability of myocardial work parameters was better in both groups. Conclusions:Myocardial work parameters obtained by PSL are early and sensitive parameters for evaluating left ventricular systolic function impairment in patients with hyperglycemia during pregnancy which can provide reliable and objective quantitative indicators for early clinical intervention and improvement of prognosis.