Evaluation of the Xpert MTB/RIF assay for diagnosis of tuberculosis and rifampin resistance in county-level laboratories in Hunan province, China / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The Xpert MTB/RIF showed high sensitivity and specificity in previous studies carried out in different epidemiological and geographical settings and patient populations in high-burden tuberculosis (TB) countries. However, there were little data obtained by validation or demonstration study of the assay in China. In this study, the performance of Xpert MTB/RIF was investigated in two county-level laboratories in Hunan Province, China.</p><p><b>METHODS</b>Consecutive patients with suspected pulmonary tuberculosis (PTB) and suspicion for multidrug-resistant tuberculosis (MDR-TB) were enrolled. For each patient suspected to have PTB, three sputum specimens (one spot sputum, one night sputum, and one morning sputum) were collected and each sputum was tested with smear microscopy, Löwenstein-Jensen (LJ) culture, and Xpert MTB/RIF test. For comparison across subgroups and testing methods, 95% confidence intervals were calculated. All analyses were done with SPSS 16.0, and P < 0.05 was regarded as significant.</p><p><b>RESULTS</b>For case detection, the sensitivity of Xpert MTB/RIF was 100% for smear- and culture-positive TB and 88.6% for smear-negative and culture-positive TB; the overall sensitivity was 94.5% for all culture-positive patients. The specificity was 99.8%. The sensitivity of Xpert MTB/RIF assay was 22.0% in clinical TB patients and the specificity reached 100.0% in the group of patients who are infected with nontuberculous mycobacteria. For the detection of rifampin resistance, the sensitivity of MTB/RIF RIF-resistance detection was 92.9%, and the specificity was 98.7%. Of the 26 Xpert MTB/RIF-positive and RIF-resistant patients confirmed by LJ proportion tests, 20 (76.9%) patients were infected by MDR-TB.</p><p><b>CONCLUSIONS</b>The Xpert MTB/RIF assay is a highly sensitive and specific method for diagnosis of TB and RIF resistance, which will enable it to have the potential to be used in county-level laboratories and lead to the reduction of the infectious pool and improvements in TB control in China. Further evaluations in county-level laboratories for implementing the assay are still required.</p>

Effect of fluorouracil combined with FK228 on the proliferation, apoptosis and Fas mRNA level in HepG2 hepatoma cell lines / 中南大学学报(医学版)

OBJECTIVE@#To explore the effect of fluorouracil (FU) combined with epigenetic drug FK228 (depsipeptide FR901228) on the proliferation, apoptosis and Fas mRNA level in HepG2 hepatoma cell lines.@*METHODS@#There were 4 groups in this experiment: an untreated group, an FK228 treated group, a FU treated group,and a FU combined with FK228 group.Tetrazolium salt colorimetry (MTT) assay was used to assess the cell inhibition rate. Q value of Kingos formula and multi-factor analysis of variance (ANOVA ) were used to judge the combination treatment effect,and flow cytometry was used to detect the apoptosis rate. Fas mRNA level was analyzed by RT-PCR.@*RESULTS@#FK228 or FU would inhibit the growth of HepG2 cells in a concentration-dependent and time-dependent manner. Cell inhibition rates of HepG2 were significantly enhanced in the FU combined with FK228 group, compared with that in the FU treated group alone (P<0.05). Both Q values were more than 1, the 2 drug combinations showed interaction,and FU combined with FK228 had synergistic effect.Compared with the FK228 treated group and the FU treated group, apoptosis rate of HepG2 cells was significantly increased (P<0.05), and the Fas mRNA level was up-regulated in HepG2 cells in FU combined FK228 group (P<0.05).@*CONCLUSION@#Combination of FK228 and FU can enhance the proliferation inhibition and apoptosis induction of FU in hepatoma cell lines, up-regulate the Fas mRNA level, and increase the sensitivity of hepatoma cell lines to FU.