Exploring the binding effect and mechanism of glycyrrhizin to ovomucin by combining spectroscopic analysis and molecular docking.

Ovomucin (OVM) is an ideal natural macromolecular glycoprotein extracted from eggs with good adhesion. Based on the defect that glycyrrhizin (GL) has good antiviral activity but fast metabolism, this study aimed to explore the binding effect and mechanism of GL to OVM, using multi-spectroscopic techniques, isothermal titration calorimetry (ITC), and molecular docking. The adhesion ability of OVM to the hydrophilic interface and GL was first demonstrated by dual polarization interferometry (DPI) analysis and binding capacity assay, and the OVM-GL complex exhibited a similar affinity for the spike protein of COVID-19. The spectroscopic results show that GL can quench the inherent fluorescence and change the glycosidic bond and secondary structure of OVM. The ITC measurements suggested that the binding was exothermic, the hydrogen bond was the dominant binding force for forming OVM-GL. Finally, molecular docking results indicated that GL has hydrogen bond interaction with several amino acid residues located in α-OVM and ß-OVM while embedding into the hydrophobic pocket of OVM via hydrophobic interactions. In conclusion, OVM can adhere to the hydrophilic interface and bind to GL through hydrogen bonding and hydrophobic interactions to form a stable complex, that is expected to be helpful in virus prophylaxis.

Analysis of adverse reactions of blood transfusion in patients with hematological diseases / 白血病·淋巴瘤

Objective:To explore the causes and preventive strategies of adverse reactions of blood transfusion in patients with hematological diseases.Methods:The clinical data of 150 hematological patients who received 5 184 cases of blood transfusion in Beijing No.6 Hospital from January 2014 to December 2017 were retrospectively analyzed. The blood transfusion adverse reaction reporting forms were collected, and the content of the form included the basic information of the patient, diagnosis, blood transfusion type, blood transfusion time, blood transfusion history, pregnancy history, adverse reaction history of blood transfusion as well as detailed records of clinical symptoms. The blood bank summarized the blood transfusion adverse reaction reporting forms every week.Results:A total of 112 cases of adverse reactions occurred in 5 184 cases of blood transfusion, the incidence rate was 2.16%. Sixty-eight cases (1.32%) had anaphylaxis, mainly caused by platelet transfusion, and 44 cases (0.85%) had fever, mainly caused by transfusion of red blood cells suspension, and no other adverse reactions were found. The incidence rates of adverse reactions of blood transfusion in patients with blood transfusion history and anaphylaxis history were significantly higher than those in patients without blood transfusion history and anaphylaxis history, and the differences were statistically significant [2.34% (102/4 350) vs. 1.20% (10/834), χ2 = 6.899, P = 0.009; 3.06% (98/3 200) vs. 1.42% (14/984), χ2 = 7.767, P = 0.005]; the incidence rate of adverse reactions of blood transfusion in female patients was significantly higher than that in male patients, and the difference was statistically significant [2.82% (60/2 126) vs. 1.70% (52/3 058), χ2 = 8.356, P = 0.004]; there was no significant difference in the incidence rate of adverse reactions of blood transfusion between patients < 18 years old and ≥ 18 years old [1.16% (3/259) vs. 2.21% (109/4 925), χ2 = 1.295, P = 0.255]. Conclusions:The main manifestations of adverse reactions of component blood transfusion are anaphylaxis and non-hemolytic fever. Clinical medical staff must carefully control the blood transfusion indications and select the appropriate blood components to reduce the adverse reactions of blood transfusion and ensure the safety of blood transfusion.