Evaluation of Dynamic Changes of IgG and IgM in COVID-19 Patients by Different Detection Methods

Objective: To analyze the dynamic evaluation of chemiluminescence, colloidal gold, and immunofluorescence chromatography in detecting antibodies in COVID-19 patients within four weeks of infection, and to provide evidence for clinical application. Method: 74 patients with confirmed SARS-COV-2 infection in the local area were selected as the experimental group, while 231 patients with negative SARS-COV-2 results but not vaccinated with Covid19 vaccine were selected as the control group;during the first, second, third, and fourth weeks after enrollment in the experimental group, three methods were used to detect SARS-COV-2 IgG and IgM in patients’ blood: chemiluminescence method, colloidal gold antibody method, and immuno-fluorescence chromatography. In the control group, three methods were used to detect SARS-COV-2 IgG and IgM during physical examination for SARS-COV-2 nucleic acids. The ROC curve was drawn to analyze the value of each indicator in predicting SARS-COV-2 infection, and the kappa method was used to analyze the consistency of the detection results of each indicator. Results: There was no significant difference in the positive rates of SARS-COV-2 IgM and IgG antibodies detected by chemiluminescence, colloidal gold, and immunofluorescence chromatography during the four-week period (P > 0.05). The positive rates of SARS-COV-2 IgM and IgG antibodies detected by the three methods during the first week of infection were not higher than 60%;when the three methods were used to detect SARS-COV-2 IgM and IgG in vivo, the AUC diagnosed by the test results was less than 0.80 at the first week, the diagnostic efficacy of the three methods was above 0.95 from the second week to the fourth week, and the diagnostic efficacy of the three methods was higher than 0.97 at the fourth week. The diagnostic efficacy of the three methods was comparable;the three methods for detecting SARS-COV-2 IgM and IgG antibodies showed high consistency in four cycles. Conclusion: Chemiluminescence, colloidal gold, and immunofluorescence chromatography are highly consistent in the detection of SARS-COV-2 IgM and IgG antibodies, and can be used as an auxiliary diagnosis and efficacy observation of novel coronavirus infections according to the needs, but the positive rate of infected people in the first week is low.

Evaluation of Clinical Application of Chemiluminescence and Real-time,Fluorescence-based Quantitative PCR in Diagnosis of Epstein-Barr Virus lnfection

Objective:To compare the effects of clinical application of chemiluminescence and real-time,fluorescence-based quantitative PCR in the detection Epstein-Barr virus(EBV).Methods:The data of chemiluminescence and real-time fluorescent quantitative PCR.fromipaEsfwo were suspected of being infectea w1tn rito1 roro January 2016 to January 2019 in our hospital were analyzed.The specific stage of EBV infection was analyzed,and the differences in results of the two detection methods were compared.Results:Chemiluminescence method was used to detect EBV infection during the active phase.The sensitivity of the chemiluminescence method was 76.7%(56/73)and the real-time quantitative PCRmethod was 90.4%(66/73).There was a statistical difference between the two detection methods(P<0.05).Conclusion:There was no statistical difference in positive predictive values between the chemiluminescence method and the real-time,fluorescence-based quantitative PCR method in the detection of EBV infection,but the sensitivity of chemiluminescence method is slightly lower than the real-time quantitative PCRmethod.It is noteworthy that chemiluminescence method is convenient and fast while the real-time,fluorescence-based quantitative PCR method is more accurate,which can provide a more accurate reference for clinical treatment.

Detection of IgM and IgG Antibodies in Mice with Hepatitis C Virus by Magnetic Particle Chemiluminescence Method

Objective:To explore the application value of magnetic particle chemiluminescence method in the detection of hepatitis C virus(HCV)IgM,IgG and other antibody indicators in mice.Methods:A total of 90 mice with HCV were selected as the research objects.All the mice were tested for HCV IgM and IgA antibody,and then their venous blood samples were taken to detect the antibody index by enzyme-linked immunosorbent assay,magnetic particle chemiluminescence method and indirect agglutination method,and the results and positive rates of the three groups were compared.Results:There was no significant difference in the positive rate among the three groups(P>0.05).The specificity,accuracy and sensitivity of indirect agglutination test for IgM were 90.79%,80.00%and 30.00%,respectively.The specificity,accuracy and sensitivity of magnetic particle chemiluminescence assay were 97.44%,93.33%and80.00%,respectively.The specificity,accuracy and sensitivity of indirect agglutination assay were significantly lower than those of magnetic particle chemiluminescence assay(P<0.05).For IgA,the specificity,accuracy and sensitivity of indirect agglutination assay were 90.67%,78.66%and 20.00%,respectively.The specificity,accuracy and sensitivity of magnetic particle chemiluminescence assay were 96.25%,92.35%and80.00%,respectively.The specificity,accuracy and sensitivity of indirect agglutination assay were lower than those of magnetic particle chemiluminescence assay,and the difference was statistically significant(P<0.05).Conclusion:The magnetic particle chemiluminescence method is more effective in the detection of IgM,IgG and other antibodies in mice with HCV.

Seasonal variability of ambient NH_3, NO, NO_2 and SO_2 over Delhi

We present the diurnal and seasonal variability of ambient NH3, NO, NO2 and SO2 over Delhi, India. Ambient NH3, NO and NO2 were measured continuously during winter, summer and autumn seasons using NH3- and NOx-analyzer, which operates by chemiluminescence method with a higher estimation efficiency （〉 90%） than the chemical trap method （reproducibility 4.7%）. Prominent diurnal, day-to-day and seasonal variations of ambient mixing ratio of NH3, NO, NO2 and SO2 were observed during the study period. Seasonal variation with higher mixing ratio in winter was observed for all measured trace gases except NO. Day-night variation of all measured trace gases observed was higher in winter in comparison with summer. Late morning increase in NO2 mixing ratio might be attributed to conversion of NO to NO2 with the interaction ofO3.