Role of tumor necrosis factor-alpha in the anti-HBV activity of tetracycline / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study the role of tumor necrosis factor-alpha (TNFalpha) in the anti-replication effects of tetracycline (Tet) on hepatitis B virus (HBV).</p><p><b>METHODS</b>The Tet-dependent regulatory fragment (TO) was PCR amplified from the pcDNA4TM/TO vector, inserted into the pUC118 cloning vector, and verified by sequencing. The counterpart fragment in the pVITRO3 expression vector, which contains two multiple cloning sites (MCSs), was replaced with the confirmed TO to generate a pVITRO3-TO vector. The Tet repressor (TR) gene from the pcDNA6/TR regulatory vector was incorporated into one MCS of pVITRO3-TO and the TNFalpha gene was subsequently incorporated into the other MCS. The resultant vector, pVITRO3-TOTR-TNFalpha, was transiently transfected into HepG2 cells. TNFalpha expression from the vector was induced by exposure to various concentrations of Tet and measured by enzyme-linked immunosorbent assay to determine the appropriate Tet concentration for experimentation. To investigate whether Tet inhibits TNFalpha expression as a mechanism of its anti-replication activity against HBV, the HepG2.2.15 cell line stably transfected with pVITRO3-TOTR-TNFalpha was used as an HBV replication model. Levels of hepatitis B e antigen (HBeAg) and hepatitis B surface antigen (HBsAg) were detected by immunoassay. HBV DNA level was detected by fluorescence quantitative PCR.</p><p><b>RESULTS</b>The TNFalpha expression from the newly constructed pVITRO3-TOTR-TNFalpha vector was Tet-controllable in the eukaryotic cells examined. The optimal concentration of Tet for the experimental system was 1.0 mug/ml. HBsAg and HBeAg expression was down-regulated in the HepG2.2.15 cells stably transfected with the pVITRO3-TO-TR-TNFalpha vector. After incubation with Tet for 1, 3 and 5 days, the inhibition rate of HBsAg was 2%, 1.1% and 0, compared to 14.8%, 11.5% and 28.4% in the non-Tet control group. The corresponding inhibition rates of HBeAg were 50.0%, 26.7% and 47.9%, compared to 0.3%, 1.6% and 0.0%, in the control group. HBV DNA levels in the cells and the cell culture supernatants exposed to Tet were decreased by 70.3% and 79.9%, respectively. TNFalpha inhibited production of HBsAg mRNA.</p><p><b>CONCLUSION</b>A Tet-dependent regulatory fragment double-expressing TNFalpha single vector system was constructed successfully, achieving controllable TNFalpha expression in both transiently transfected eukaryotic cells and stable cell lines. In this HBV cell model system, Tet-induced overexpression of human TNFalpha inhibited HBV DNA replication and reduced HBsAg and HBeAg expression. Inhibition of HBV transcription may be a key role of TNFalpha against HBV replication.</p>

Role of serum procalcitonin assay for diagnosis of spontaneous bacterial peritonitis in end-stage liver diseases / 中国医学科学院学报

<p><b>OBJECTIVE</b>To explore the clinical value of serum procalcitonin (PCT) for predicting spontaneous bacterial peritonitis (SBP) in end-stage liver diseases.</p><p><b>METHODS</b>The clinical data of 362 ascitic inpatients with end-stage liver diseases who had underwent serum PCT assay in our department from March 2011 to June 2013 were analyzed retrospectively. These patients were then divided into SBP group (n=178) and non-SBP group (n=184). The dynamic changes of the PCT values upon admission and after antibiotic treatment were compared. The receiver operating characteristic curve was drawn to identify the optimal cut-off value of serum PCT in diagnosing SBP.</p><p><b>RESULTS</b>The positive rate of bacteria culture in ascites was only 4.6% (4/87) in SBP group. The median value of serum PCT was 0.73 and 0.15 ng/ml in SBP group and non-SBP group (Z=-11.9, U=0.000), respectively, before antibiotic treatment. In the SBP group, the median value of serum PCT was 1.73 ng/ml in 13 patients with positive culture findings, which was higher than the overall median value in SBP group. Among patients who were responsive to the antibiotic therapy, the median values of serum PCT were 0.40(n=46), 0.32(n=19), and 0.33 ng/ml(n=25), respectively, 3, 5, and 7 days after the effective antibiotics treatment, which were significantly lower than the pre-treatment levels [0.86(Z=-5.91, U=0.000), 0.72(Z=-3.10, U=0.002), and 0.79 ng/ml(Z=-4.37, U=0.000), respectively]. ROC analysis showed that a serum PCT value of more than 0.462 ng/ml had a sensitivity of 83.7% and a specificity of 94.9%(AUC:0.95, 95%CI:0.93-0.97, P=0.00) in diagnosing SBP in patients with end-stage liver diseases.</p><p><b>CONCLUSIONS</b>Ascitic fluid positive rate is low in SBP patients. Serum PCT is a sensitive and specific marker for predicting peritoneal bacteria infection in end-stage liver disease patients with ascites. Higher serum PCT can be expected in these patients with heavier infections, it can also be used to evaluate the effectiveness of anti-bacteria therapies.</p>

Effects of in vitro conditions on release behavior of different types of sustained and controlled release formulations of breviscapin / 药学学报

Insoluble breviscapin was chosen as the model drug. Bi-layer osmotic pump technology and gel matrix technology were used to prepare the breviscapin sustained and controlled release preparations. Dissimilarity factors (f1) and similarity factors (f2) were applied as similar judgment index to compare the effects of in vitro conditions on the release behavior of different types of breviscapin sustained and controlled release preparations. The tolerance of in vitro release conditions of bi-layer osmotic pump technology and gel matrix technology were studied. The results showed that in vitro release conditions have a greater impact on the gel matrix sustained release formulations, while have almost no effects on the osmotic pump controlled release formulations. Therefore, osmotic pump controlled release technology is less affected by the drug release environment. And it has a very good application prospect.