The role of heparin-binding protein in predicting bacterial infection in traumatic intracerebral hemorrhage / 中华急诊医学杂志

Objective:To investigate the role of heparin-binding protein (HBP) as a predictor of early bacterial infections in patients with traumatic intracerebral hemorrhage.Methods:Patients with traumatic intracerebral hemorrhage admitted to the Emergency Department of the First Hospital of Shanxi Medical University from September 2021 to June 2022 were collected prospectively. Patients with bacterial infection diagnosed by pathogenic examination were classified as the infected group, and those with negative pathogenic examination were classified as the non-infected group. Peripheral blood HBP counts were measured within 48 h of admission, and general information and relevant laboratory tests were collected. The differences of the indicators between the two groups were compared, the receiver operating characteristic (ROC) curve was drawn, the predictive value of the indicators for patients with co-infection was assessed, and the valuable predictors were screened out using multivariate logistic regression analysis.Results:Eighty-five patients [44 males and 41 females, aged (55.09±1.18) years] , were included in the study. Among the patients included in the study, 39 patients had bacterial infection and 46 were non-infected. Patients in the infected group were older , and had more surgeries, higher respiratory rate and injury severity score, and higher levels of HBP [(33.00±3.49) ng/mL vs. (16.27±1.61) ng/mL, P<0.001], leukocytes, and neutrophils [(15.32±3.19) ×10 9/L vs. (6.69±0.57) ×10 9/L, P=0.005] than in the non-infected group, while the Glasgow Coma Scale [(8.72±0.63) vs. (11.37±0.48), P=0.001] was lower than that in the non-infected group, with statistically significant differences (all P<0.05). There was no significant differences in lymphocytes, red blood cells, platelets, calcium, procalcitonin and coagulation indexes between the two groups (all P>0.05). Logistic regression analysis showed that neutrophils ( OR=1.252, 95% CI: 1.075-1.457, P=0.004) and HBP ( OR=1.081, 95% CI: 1.025-1.141, P=0.004) were independent risk factors for infection in patients with traumatic cerebral hemorrhage. The area under ROC curve for HBP of diagnosing early co-infection in patients with traumatic intracerebral hemorrhage was 0.82 (95% CI: 0.71-0.88), the sensitivity was 92.31%, and the specificity was 52.17%. Conclusions:HBP is a valuable predictor of early traumatic intracerebral hemorrhage complicated with bacterial infection in the emergency department, and has a good supplementary value to the existing test indicators.

Vaccine pretreatment for quantification of 146S antigen in foot-and-mouth disease vaccines by high performance size exclusion chromatography / 生物工程学报

We developed a pre-treatment method to remove interfering substances during quantification of 146S antigens in foot-and-mouth disease (FMD) vaccines by high performance size exclusion chromatography (HPSEC). Three methods, including ultracentrifugation, PEG precipitation and nuclease digestion, were optimized and compared for removal efficiency of the interfering impurities in FMD vaccines. Under optimized conditions, the 146S contents in two batches of FMD vaccines were determined to be 7.1 and 7.6 μg/mL by ultracentrifugation, 9.7 and 10.4 μg/mL by PEG precipitation, and 10.5 and 10.4 μg/mL by nuclease digestion. The optimal condition for nuclease digestion using Benzonase determined by response surface method was as follows: appending Benzonase into 200 μL of antigen phase to a final concentration of 421 U/mL and incubating at 25.1 °C for 1.29 h. This method has advantages including efficient removal of the interfering impurities, fast processing speed, and mild operating conditions. Then 12 bathes of FMD vaccines with different serotypes produced by 4 manufacturers were tested to verify the established treatment method. Results showed the method was applicable to various FMD vaccines with good reproducibility (RSD<5.3%, n=3). The developed method removed interference from impurities during quantification of 146S, and therefore would broaden the application of HPSEC in vaccine quality control and ensure the accuracy and reliability.

Using size-exclusion chromatography to quantify the 146S antigen in inactivated foot-and-mouth disease vaccine / 生物工程学报

The aim of this study is to quantify the 146S antigen in foot-and-mouth disease virus (FMDV) inactivated vaccine by size-exclusion chromatography (SEC). The analysis was performed on a TSKgel G4000SWXL column (7.8 mm×30 cm), with a pH 7.2 buffer salt system as the mobile phase. The flow rate was 0.6 mL/min, the injection volume was 100 μL and the detection wavelength was 259 nm. The calibration curve was established by using purified inactivated FMDV (serotype O) 146S antigen; 3 batches of vaccine formulated by inactivated antigen solution were tested to verify the accuracy, reproducibility, specificity and tolerability of the method. At last 16 batches of vaccine were determined by the SEC method. Results showed a good linearity between peak area and concentration of 146S antigen in the range between 0.56 and 67.42 μg/mL (R2=0.996, n=10), and the average recovery rate of 146S antigen in the 3 batches of vaccine formulated in lab were 93.6% (RSD=2.7%, n=3), 102.3% (RSD=2.6%, n=3), and 95.5% (RSD=5.1%, n=3). The method was proved accurate and reliable with good reproducibility (RSD=0.5%, n=6), and applied to determine 16 batches of the commercial FMDV vaccine. According to the above results, the SEC method is high effective for 146S antigen quantify in the inactivated FMDV vaccine and would provide strong support for the vaccine quality control.