The capability of hepatitis B virus (HBV) to increase the transcription of the human hepatic inducible nitric oxide synthase (iNOS) by transactivating its promoter has been studied. We have observed by reverse-transcription polymerase chain reaction (RT-PCR) that although the mRNA for the iNOS was almost undetectable in the human hepatoblastoma cell line, HepG2, it was constitutively expressed in the 2. The hepatitis B virus (HBV), the prototype member of the Hepadnaviridae family of animal viruses, is a noncytopathic enveloped virus that causes acute and chronic liver disease and is related to the development of hepatocellular carcinoma in chronically infected patients. 1 The HBV genome is a 3.2-kb-long circular partially double-stranded DNA molecule. 2 The HBV DNA contains four overlapping open reading frames (ORFs) that encode the structural and nonstructural viral proteins. Among them, the X protein (pX) encoded by the ORFX activates the transcription of HBV and other viral and cellular promoters in vitro. 3 Furthermore, pX transactivates gene promoters containing binding motifs for nuclear factor-B (NF-B) among other transcription factors. 4 Nitric oxide (NO) is produced during the conversion of L-arginine to L-cytruline, a process that is catalyzed by NO synthase. 5 There are three different isoforms of this enzyme. 6 Two of them (cNOS) are constitutively expressed in neuronal and endothelial cells, while the third, inducible isoform (iNOS) is expressed in macrophages and hepatocytes in response to several cytokines, tumor necrosis factor ␣ (TNF-␣), interleukin-1␤ (IL-1␤), interferon gamma (IFN-␥), and endotoxins. [7][8][9] It has been reported that woodchucks chronically infected by the woodchuck hepatitis virus (another member of the Hepadnaviridae family) show an increase in NO production and endogenous formation of the DNA damaging agent, N-nitrosodimethylamine in vivo. 10,11 However, the mechanism responsible for the increase in NO production remains unclear. Recently, an increase in iNOS mRNA levels in hepatoma cells transfected with a pX expression plasmid has been reported. 12 Because the promoter of the human hepatic iNOS contains functional binding sites for NF-B, 13 it may be hypothesized that HBV pX protein can transactivate this promoter.In the present report, we have studied if HBV can transactivate the hepatic iNOS gene promoter and whether pX or other viral-encoded proteins are responsible for this transactivation. MATERIALS AND METHODSCell Lines. The Chang liver cell line, which is derived from nonmalignant human liver tissue, the human hepatoblastoma cell line, HepG2, and the 2.2.15 cell line (kindly provided by Dr. Manuel Ló pez-Cabrera, Molecular Biology Unit, Hospital de la Princesa, Madrid, Spain), which is derived from the HepG2 cell line and which is stably transfected with a dimer of the complete HBV genome, 14 were used. To check whether 2.2.15 cells produce HBV proteins, hepatitis B surface (HBsAg) and e (HBeAg) antigens were tested in culture supernatants by commercial enzyme im...

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Nitric oxide is a free radical gas molecule which may be implicated in antiviral defense. However, there is no information about its possible role in chronic viral hepatitis B and C. In this study we have analyzed the serum levels of NO2- (as an index of nitric oxide generation) from patients with chronic viral hepatitis B and C and relationship of same with the response to interferon therapy. Serum samples were analysed from 61 patients with chronic hepatitis B, 60 patients with chronic hepatitis C, 11 with chronic liver disease of nonviral origin, and 23 healthy controls. Levels of NO2- were statistically higher in healthy controls (P < 0.001) than in patients with chronic liver disease. No relation was found between NO2- and viremia or response to interferon therapy in patients with chronic hepatitis B. In contrast in chronic hepatitis C, responder patients had significantly higher NO2- than nonresponders (P < 0.01). With respect to the relation between NO2- levels and liver damage, patients with cirrhosis had lower NO2- levels than the rest of the patients (P < 0.001). In conclusion, patients with chronic viral hepatitis have low serum NO2- levels.

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Intravascular ultrasound (IVUS) is an imaging modality more sensitive for defining suboptimal stent deployment issues compared with conventional angiographic imaging. We report on a patient with unstable angina who underwent stent deployment using IVUS guidance. Despite an acceptable angiographic result, intrastent thrombus, incomplete expansion and an edge/marginal dissection were seen by IVUS examination. Both the incomplete expansion and the intrastent thrombus were successfully treated. The dissection, however, was not treated in the catheterization laboratory. This mechanical injury pattern at the stent edge led to vessel occlusion 4 h post-procedure.