1.Characteristics of pncA gene in multidrug-resistant Mycobacterium tuberculosis isolates and its correlation with drug resistance to pyrazinamide.
Chuang-Yue HONG ; Feng WANG ; Jing GUI ; Xiao-li LIU
Chinese Journal of Preventive Medicine 2012;46(5):436-439
OBJECTIVETo understand the characteristics of pncA gene in multidrug-resistant Mycobacterium tuberculosis isolates and its correlation with drug resistance to pyrazinamide.
METHODSA total of 127 clinical isolates of multidrug-resistant mycobacterium tuberculosis were collected from Shenzhen from year 2007 to 2009. PZA susceptibility was determined by the BACTEC MGIT 960 PZA method. Pyrazinamidase (PZase) activity testing and pncA gene sequencing were performed in all the isolates. The type and frequency of mutations in pncA were determined. Correlation analysis among PZA susceptibility and PZase activity, pncA mutation was performed.
RESULTSAmong the 127 isolates, 62 isolates (48.8%) were found resistance to PZA. Among the 62 PZA resistant isolates, 45 isolates which had various pncA mutations were negative for PZase. Mutation rate was 77.4% (48/62) in total PZA resistance isolates. Different types of 48 resistant isolates were identified in the pncA gene, including base substitution (33 isolates), frame shift mutation (12 isolates) and codon mutation (3 isolates). No mutations except one isolate (N11D) existed in all PZA-susceptibility isolates which were positive for PZase. A total of 5 mutations which have not been described previously were found as follows: H57P, P62Q, G108R, D110Y and G162V. The correlation among the PZA susceptibility and the PZase activity (r = 0.895, P < 0.05), the pncA mutation (r = 0.779, P < 0.05) were significant in 127 multidrug-resistant isolates.
CONCLUSIONA high diversity of pncA gene mutation was found among PZA resistant strains of MTB. This study revealed five new mutations of the pncA gene that were not previously described, which scattered in the hot-spot regions located in the metal coordination site and active site of the enzyme. Mutations had a high correlation with the PZA resistance.
Antitubercular Agents ; pharmacology ; DNA, Bacterial ; genetics ; Humans ; Mutation ; Mycobacterium tuberculosis ; drug effects ; genetics ; isolation & purification ; Pyrazinamide ; pharmacology ; Tuberculosis, Multidrug-Resistant ; genetics ; microbiology
2.Exploration on the relationship between pathogenesis for yin-deficiency of acute myocardial infarction and immediate prognosis as well as its mechanism.
Nan-yi LI ; Yue-yi LI ; Chuang-xiong HONG
Chinese Journal of Integrated Traditional and Western Medicine 2004;24(5):400-403
OBJECTIVETo study the relationship between pathogenesis for Yin-deficiency of acute myocardial infarction (AMI) and immediate prognosis as well as its neuro-endocrine mechanism.
METHODSAccording to the TCM standard of Syndrome Differentiation of Deficiency Syndrome, 194 patients with AMI were classified into the typical Yin-deficiency group (n = 26), the non-typical Yin-deficiency group (n = 61) and the non-Yin-deficiency group (n = 107). Their venous blood samples were collected in the morning while lying on their backs to detect plasma levels of adrenaline, noradrenaline, aldosterone, atrial natriuretic peptide (ANP), corticoid and myocardial enzymes, as well as their hospitalization days and mortality in hospitalized period were calculated and compared in the three groups, with the 30 healthy persons as control.
RESULTSLevels of serum creatine phosphokinase, creatine phosphokinase isozyme, plasma adrenaline, noradrenaline, aldosterone, hospitalization days and mortality were higher in the Yin-deficiency groups than in the non-Yin-deficiency group (P < 0.05, P < 0.01). As compared the indexes between the typical and the non-typical Yin-deficiency groups, significant difference only showed in plasma aldosterone and ANP, which was significantly higher in the former (P < 0.05, P < 0.01). Plasma corticoid level was insignificantly different between the Yin-deficieny groups.
CONCLUSIONPatients with AMI of Yin-deficiency type was severer in myocardial damage, with longer hospitalization period and higher mortality, it is probably due to the hyper-activated sympathetic-adrenaline system and strengthened activity of aldosterone in them.
Adult ; Aged ; Aged, 80 and over ; Creatine Kinase ; blood ; Diagnosis, Differential ; Female ; Humans ; Male ; Medicine, Chinese Traditional ; Middle Aged ; Myocardial Infarction ; diagnosis ; Prognosis ; Yin Deficiency ; diagnosis ; etiology
3.Expression and relevance of serum IgE,IgE receptors and autoantibodies in patients with chronic urticaria
Yue YIN ; Chuang GAO ; Hong DANG ; Wen XU ; Xia PENG ; Yuting LIANG ; Huanjin LIAO ; Li LI
Chinese Journal of Laboratory Medicine 2020;43(4):411-415
Objective:To detect serum levels of immunoglobulin E (IgE), soluble version of the IgE-binding alpha-chain of Fcepsilon-RI (sFcεRIα), immunoglobulin G (IgG) anti-IgE, IgG anti-FcεRI in patients with chronic urticaria(CU), and to evaluate their relevanceMethods:Forty-three newly diagnosed patient with CU were enrolled. Thirty-seven patients with dermatitis or eczema and 51 healthy subjects were selected as the disease control (DC) and normal control (NC) group, respectively.Serum IgE was detected by immunoturbidimetry; serum anti-IgE, anti-FcεR Ⅰ and sFcεR Ⅰ α were determined byenzyme-linked immunosorbent assay (ELISA) methods. Statistical analysis was carried out by non-parametric test for comparisons of the above variables between groups, and by Spearman correlation analysis for assessment of relationships between the variables as well as between the variables and disease severity, and by receiver operating characteristic curve to analyze the diagnostic value of the variables.Results:Serum IgE, anti-IgE and anti-FcεRI in CU were significantly higher than that of NC.Their medians are 65.70 IU/ml vs 17.10 IU/ml,χ 2=28.541, P=0.001;0.61 vs 0.39,χ 2=27.408, P=0.001;0.64 vs 0.51, χ 2=29.102, P<0.001.Serumanti-FcεRI in CU was significantly lower than that in NC(0.64 vs 0.83,χ 2=25.869, P=0.007).The medians of serum sFcεRIα in CU, DC and NC groups were 5.74,5.38,4.50 ng/ml, respectively. The difference was not statistically significant,χ 2=3.463, P=0.177.There was a positive correlation between IgE and sFcεR Ⅰ α, anti-IgE and anti-FcεRI( r=0.455, P<0.001; r=0.611, P<0.001).No significant correlation was showed between the four variables and the course of disease or the severity of symptoms, P>0.05. The diagnostic performances of IgE, anti-FcεRI for CU were similar (AUC=0.72),which were better than that of sFcεRIα (AUC=0.61).The highest diagnostic efficacy (AUC=0.83) can be achieved by four joint tests.Anti-FcεRI is of value in differential diagnosis of CU and DC, AUC=0.7, P=0.002. Conclusion:The levels of serum IgE, anti-IgE, anti-FcεRI were significantly increased in CU patients, and these mast cell activation-related molecules have the potential to be diagnostic markers for CU.
4. An indirect ELISA method for quantitative detection of anti-IgE autoantibodies
Yue YIN ; Hong DANG ; Chuang GAO ; Xia PENG ; Yuting LIANG ; Huanjin LIAO ; Li LI
Chinese Journal of Laboratory Medicine 2019;42(9):782-786
Objective:
The accurate measurement of anti-IgE levels in patients′ serum helps for make diagnosis of chronic urticaria (CU). An indirect ELISA method for quantitative detection of IgG anti-IgE, were established.
Methods:
The serum samples and the clinical data of 75 first-diagnosed CU patients and 120 healthy controls were collected at Shanghai General Hospital during the year of 2018. In the indirect ELISA system to measure the IgG (anti-human IgE), the antigen, Human IgE Myeloma, was coated on the plate; Omalizumab (a humanized anti-human IgE antibody) was the standard, and horse radish peroxidase (HRP)-labeled anti-human IgG was the tracer. The optimum concentrations of serum and HRP-labeled anti-human IgG were determined by chessboard titration, and method evaluation was conducted. The comparison of serum anti-IgE levels in CU patients and healthy people were analyzed by Mann-Whitney U test and chi-square test. Receiver operating characteristic (ROC) curves were applied to establish the diagnostic performance of serum anti-IgE for CU.
Results:
The coating concentration of IgE was 5.0×10-4 mg/ml; serum dilution was 1∶300; enzyme-labeled antibody dilution was 1∶100 000. Standard curve was in good linearity with R2=0.996. The intra-and inter-assay coefficient of variation were 3.9%-7.5% and 6.0%-8.2%, and the recovery rate of low and high concentration samples were 95.9% and 108.4%, respectively. When hemoglobin≤1.3 g/L, triglyceride≤4.6 mmol/L, bilirubin≤171 μmol/L, no interference were observed. The limit of blank, limit of detection, and limit of quantitation were 5.8×10-4, 1.8×10-3, and 2.0×10-3 mg/ml. The linearity range was from 2.0×10-3 to 354.4 mg/ml. No Hook effect was found until anti-IgE reached 354.4 mg/ml. The anti-IgE remained stable after serum storage at 4 ℃ overnight or treated with 6 repeated freeze-thaw cycles. The anti-IgE levels in CU patients [19.0(1.9, 58.6)mg/ml] were significantly higher than those in healthy controls [0.7(0.002, 11.1)mg/ml] with P<0.001. When cut-off value was set as 15.3 mg/ml, in this method, the positive rate of CU patients (54.7%) was significantly higher than these of healthy controls (18.3%) (P<0.001, AUC=0.736).
Conclusions
The indirect ELISA method for serum anti-IgE measurement was successfully established. Anti-IgE autoantibodies in serum would be used in the diagnosis of CU.