OBJECTIVE:To prepare sulfadiazine silver film and establish a way for its quality control.METHODS:Polyvinyl alcohol was used as the main excipients for the preparation of film;the dead-stop titration was used to determine the content of sulfadiazine silver;the stability of the film sample was observed.RESULTS:The content of sulfadiazine silver was 98.9%～100.7%,the average recovery rate was 100.6%,RSD=0.69%(n=6).CONCLUSION:The prepared sulfadiazine silver film is stable in quality,accurate in content,simple in preparation and the testing method is fast.

This study was intended to establish a method of preparation of recombinant human insulin, with (His)6-Arg-Arg-human proinsulin (RRhPI) expressed by Escherichia coli. After DEAE-Sepharose Fast Flow ion-exchange chromatography, Sephadex G-25 chromatography and refolding, enzyme cleavage and Superdex 75 size exclusion chromatography,the RRhPI expressed by Escherichia coli in inclusion body form was converted to human insulin. The obtained recombinant human insulin was analyzed by SDS-PAGE, HPLC, amino acid composition analysis and bioidentity test (mouse convulsion test). The results indicate that our obtained preparation is highly purified, active recombinant human insulin.
Chromatography, High Pressure Liquid ; Escherichia coli ; genetics ; metabolism ; Humans ; Insulin ; biosynthesis ; genetics ; isolation & purification ; Proinsulin ; biosynthesis ; genetics ; Recombinant Proteins ; biosynthesis ; genetics

Objective To explore the relationship between the outpatient visits for adult asthma and air pollution in a tertiary hospital in Hefei. Methods The number of outpatient visits for asthma in a tertiary hospital in Hefei from 2014 to 2020 was collected. The air pollutant data was obtained through the Hefei Air Monitoring Station, and the meteorological indicators of the same period were collected through the China Meteorological Network. The R statistical software was used to establish a generalized additive model to analyze the lag effect of air pollution on the number of outpatient visits for asthma. Results From 2014 to 2020, there were 7 220 asthma outpatients in the tertiary hospital in Hefei, including 3104 males and 4 116 females, 3 798 patients in warm season, and 3 422 patients in cold season. During the period, the average concentrations of SO₂, NO₂, CO, O₃, PM₁₀, and PM_2.5 were 11.9μg/m³, 40.1μg/m³, 0.9 mg/m³, 87.3μg/m³, 81.3μg/m³, and 55.7μg/m³, respectively. The results of the single-pollutant model showed that every 10μg/m³ increase in SO₂ concentration increased the risk of asthma by 0.74% (95%CI: 0.22%-1.29%), and the effect was the greatest on Lag2 day. NO2 increased the risk of asthma by 0.31% (95%CI: 0.13%-0.49%), with the greatest effect on Lag0 day. The analysis of the dual pollutant model found that whereas the effect of SO₂ decreased after the incorporation of NO₂, the effect increased after the incorporation of CO, O₃, PM₁₀, or PM_2.5, respectively. The effect of NO₂ on asthma decreased after the incorporation of SO₂, whereas the effect on asthma increased after the inclusion of CO, PM₁₀, or PM_2.5. Stratified analysis of cold and warm seasons showed that the effect of NO₂ on asthma was the greatest in lag0 in cold season. The effect of SO₂ was higher in cold season than in warm season, and it was the highest in lag2. The gender stratification analysis showed that the effects of SO₂ and NO₂ on male asthma were higher than those on females. Conclusion From 2014 to 2020, the increase of SO₂ and NO₂ concentrations in Hefei is positively correlated with the risk of asthma in the outpatient department of a tertiary hospital. The effect has a certain lag. It is of great significance to formulate relevant preventive measures for the occurrence and attack of asthma.

Objective To investigate the preventive therapeutic effect and possible mechanism of single chain variable fragments chimeric protein (SD) of ovalbumin epitopes internalizing receptor DEC-205 antibody on food allergy in mice. Methods Mice were randomly divided to five groups (control, PBS, scFv DEC 100 μg, SD 50 μg, SD 100 μg) and treated for 24 hours before OVA administration. After challenge, the serum level of OVA-specific IgE, IgG1, IgG2a and IL-4 were detected by ELISA. Infiltration of eosinophils and mast cells in the jejunum was observed by HE staining and toluidine blue staining respectively. The bone marrow of tibia and femur was isolated and cultured to obtain immature dendritic cells(BMDCs), which were further treated with LPS (10 ng/mL), TSLP (50 ng/mL), scFv DEC protein (1000 ng/mL) and SD protein (10,100,1000)ng/mL for 24 hours, and the IL-10 level of supernatant was assayed by ELISA. Results Compared with PBS group, the number of SD-treated mice with diarrhea was markedly reduced. The difference in rectal temperature and the levels of serum OVA-specific IgE, IgG1, IgG2a and IL-4 decreased significantly after prophylactic administration of SD; The number of eosinophils and mast cells in jejunum also decreased significantly while the IL-10 level in the supernatant of BMDCs increased significantly after SD intervention. Conclusion SD mitigates experimental FA response by fosters the immune tolerance property of dendritic cells.
Mice ; Animals ; Ovalbumin ; Interleukin-10 ; Single-Chain Antibodies/genetics* ; Immunoglobulin E ; Epitopes/therapeutic use* ; Interleukin-4 ; Food Hypersensitivity/prevention & control* ; Immunoglobulin G ; Recombinant Fusion Proteins/genetics* ; Mice, Inbred BALB C ; Disease Models, Animal