ABSTRACT
To investigate the detection threshold of Treponema pallidum specific antibody method by chemiluminescent immunoassay (CLIA) in Siemens ADVIA Centaur XP for Syphilis serological test, and compare with the results derived from CMIA, TP-WB and TPPA method. The result can serve as reference for the application of CLIA. In total 30 887 samples screened by Treponema pallidum specific antibody method were collected by Abbott architect i2000 CMIA from July 2018 to July 2019 in Yanda Hospital of Hebei Province. We selected 153 patients with the ratio of sample absorbance to critical value (S/CO) of 1-9 by CMIA screening of Treponema pallidum specific antibody as the research objects. The reverse sequence of syphilis serological detection was adopted, and TP-WB and TPPA were used as the confirmation methods respectively. MedCalc software was used to analyze the results of ROC curve, and the cut-off value was obtained. Chi square test was used to test the difference significance of counting data. The detection results of Treponema pallidum specific antibody in the same batch of serum samples were unequal by different methods. There was no significant difference between CLIA method and TPPA method, but significant difference between CLIA method with TP-WB method and CMIA method was found. TPPA test results and TP-WB test results were taken as gold standards, ROC curve analysis showed that the best diagnostic cutoff value of CLIA method was 4.01 and 16.06, respectively, and the area under the curve was 0.961 and 0.838. The suggested cutoff value of CLIA method is quite different when using different syphilis serological test methods as the gold standard, Therefore, when the S/CO value determined by CLIA is between 1.00 to 16.06, TP-WB method should be recommended as the first choice in laboratory serological test for recheck and confirmation to avoid clinical misdiagnosis.
ABSTRACT
Objective:To determine the reliability and validity of the Chinese version of Fagerstrom Test for Nicotine Dependence (FrND) scale among smoking male inpatients with schizophrenia.Methods:Two hundred and twenty smoking male inpatients,who met criteria for schizophrenia of Diagnostic and Statistical Manual of Mental Disorders,Fourth Edition (DSM-Ⅳ),were consecutively included.FTND scale and Russell's Reasons for Smoking Questionnaire (RRSQ) were used to assess subjects'severity of nicotine dependence and addiction score of the dimension of reason for smoking,respectively.According to the principle of voluntariness,37 subjects were selected and re-assessed with FTND scale after two-week interval.Reliability,correlation and factor analyses were used to examine the reliability and validity.Results:The Cronbach α (internal consistency) and two-week re-test reliability coefficients of FTND scale were 0.68 and 0.72 (P ＜0.01),respectively.The criterion related validity coefficient with addiction score of RRSQ was 0.53 (P ＜0.01).Two common factors were abstracted from the scale factor analysis,accounting for 52.4％ of the total variance.There were statistically significant differences between patients with different duration of illness,number of hospitalizations and age of smoking initiation (P ＜0.05).Conclusion:The Chinese version of FTND scale for smoking male inpatients with schizophrenia has a relatively low internal consistency and good re-test reliability,criterion related validity,construct validity and empirical validity.
ABSTRACT
Objective The truncated fibronectin-binding proteins A (Fba protein) were cloned and expressed, then animals were immunized with Fba protein and subsequently challenged with group A streptococcus (GAS) to further investigate protective antibodies induced by each domain and determine the most immunogenic domain. Methods Fba proteins, which were divided into four overlaps based on the structural domains, were truncated and expressed. The fba truncated genes were amplified by polymerase chain reaction (PCR) with SSI-9 of GAS as template, and cloned into prokaryotic expression plasmid pGEX-2T and expressed in E. coli BL-21. The products were confirmed by Western blot and purified by affinity chromatography column. Female BALB/c mice were immunized with the four truncated proteins respectively, with phosphate buffered solution (PBS) as control. The serum IgG of mice was detected by enzyme-linked immunosorbent assay (ELISA). After the third immunization, mice were challenged with fatal dose of GAS (M+ Fba+ ) to evaluate the protective rates in each group. The data were compared by analysis of variance and Fisher's exact test.Results Prokaryotic expression plasmids of pGEX-2T/FbaAl, pGEX-2T/FbaA2, pGEX-2T/FbaA3 and pGEX-2T/FbaA4 were successfully constructed and the four truncated proteins were expressed and purified successfully. Serum levels of IgG in each experimental group gradually increased with immunization with Fba protein more times. After the third immunization, the IgG titer against FbaA2 1290.2, P<0. 01). After GAS challenge, four out of eight mice were protected in FbaA2 protein group, while two out of eight mice in FbaAl protein, FbaA3 protein and FbaA4 protein groups,respectively (P<0. 05). Conclusions Four truncated Fba proteins are constructed and expressed successfully. Truncated FbaA2 protein could be able to induce strongest protective immune response.
ABSTRACT
Objective:To identify monoclonal antibody McAb2 recognizing epitope of Fba of GAS.Methods:The overlapped peptides were synthesized and their abilities to bind McAb2 were detected by dot-ELISA.The predominance amino acids specific for McAb2 were screened using phage 7 peptide library.Results:The result by dot-ELISA analysis demonstrated that the synthetized peptide,amino-acid residues 100-112~(th),could bind McAb2 with high affinity.The predominance amino acids specific for McAb2 were ITPDL,which was located in 100-110~(th)aa of Fba by panning with phage 7 peptide library.Conclusion:The domain and the predominance amino acids of Fba recognized by McAb2 is determined.The results would contribute to the research of the role of Fba on the pathogenic mechanism of GAS,the identification of function of McAb2,and the development of epitope-peptide vaccine.