Ultrasonography in the study of hepatocellular carcinoma in woodchucks chronically infected with WHV

The woodchuck hepatitis virus (WHV)/woodchuck system is studied as animal model of human hepatocellular carcinoma (HCC) induced by chronic hepatitis B virus infection. The aim of the present study was the evaluation of ultrasound (US) liver examination in woodchuck as a routine method to detect HCC nodules and to follow their growth. Sixteen woodchucks were included in the study. US liver examination was carried out in all animals using a 5 MHz convex scanner. Macroscopic and microscopic examinations were performed to evaluate the US findings. The lower limit of nodule detection by US examination was a diameter of 5 mm. Macroscopic and microscopic examinations confirmed US findings in 14 of 16 animals (86.6%). No false negative results were obtained. Increase of nodule size was faster in the early phase of tumour growth. Small nodules (16 +/- 5 mm) appeared as hypoechoic lesions with well-defined margins and homogeneous structure. Large nodules (42 +/- 19 mm) appeared as hyperechoic lesions with irregular margins, heterogeneous or of mixed pattern; microscopical examination showed different degrees of necrosis, inflammation and fibrosis inside these latter neoplasms. The hepatitis reaction was conspicuously more severe around HCC nodules. No fibrosis and/or cirrhosis were found in normal liver parenchyma surrounding tumour nodules. On the whole, US appears to be helpful in the diagnosis of woodchuck HCC even at an early stage. Serial US evaluation can be used to study the growth rate of tumour nodules during natural history or experimental HCC treatments in woodchuck.     

肝内HDAg阳性慢性肝炎病理特点探讨

用直接酶标和直接免疫荧光法在120例HBsAg阳性肝组织中检测HDAg,发现5例阳性(4.2％),其中3例活动性肝硬化,2例慢性中型活动性肝炎。另设立相对应的单纯乙型肝炎作为对照,通过光镜、电镜、免疫组化的方法,重点探讨比较丁型肝炎与单纯乙型肝炎二者肝组织学的形态变化。丁型肝炎组肝细胞灶状坏死,桥接坏死,融合性坏死的程度比单纯乙型肝炎组重,丁型肝炎组较单纯乙型肝炎组常见的组织学改变是肝细胞呈灶状微小空泡的脂肪变性及灶状嗜酸性变性。HDAg阳性肝细胞呈疏松化、核固缩,其周围未见淋巴细胞浸润。     

Mouse hepatitis virus S in weanling Swiss mice following intranasal inoculation

Three-week-old outbred mice were inoculated intranasally with a mildly pathogenic strain of mouse hepatitis virus (MHV-S). Tissues were analyzed for distribution of infectious virus, lesions, and viral antigen at intervals up to 49 days after inoculation. Sera were tested for neutralizing antibody to MHV-S. Within the first week of infection, virus was isolated from lung and brain of most mice and liver of one mouse, but not from blood, spleen, or intestine. Microscopic lesions consisted of mild olfactory mucosal necrosis, neuronal necrosis of olfactory bulbs and tracts, lymphoplasmacytic infiltrates and vacuolation in the brain, mild nonsuppurative pulmonary perivascular lymphocyte infiltration, focal interstitial pneumonia, and focal necrotizing hepatitis. The presence and distribution of MHV antigen, as determined by indirect immunofluorescence, correlated with virus recovery and acute lesions. No virus or antigen was demonstrable beyond day 7. Serum antibody was first detected on day 10, and titers peaked on day 28 after infection.     

Antibody to hepatitis B core antigen in chronic active hepatitis.

Antibody to hepatitis B core antigen (anti-HBc), which has been assumed to be a more sensitive indicator of hepatitis B virus replication than hepatitis B surface antigen (HBsAg), was detected in the sera of 26 of our 65 patients with HBsAg-negative chronic active hepatitis. Thus despite the absence of HBsAg the liver disease could be the consequence of chronic infection with hepatitis B virus in these patients. They differed, however, from a group of 35 patients with HBsAg-positive hepatitis in being older on average and having less active liver lesions. The two groups could represent either two stages of chronic infection with hepatitis B virus or two types of response to it.     

Tumor necrosis factor-alpha and interleukin-4 in the blood sera of chronic hepatitis patients

The concentration of tumor necrosis factor-alpha (TNF-alpha) and interleukin-4 (IL-4) in the blood sera of chronic hepatitis patients was, on the average, reliably higher than in the control group. A more pronounced increase in the concentration of TNF-alpha in the blood sera was observed in patients with chronic hepatitis of viral etiology in comparison with toxic hepatitis. The pronounced cytokine response of type Th2, manifested by the excessive production of IL-4, was typical for hepatitis B virus and hepatitis C virus infections, but not characteristic of hepatitis D virus infection. The replication activity of hepatotropic viruses induced a powerful cytokine response. In the presence of active virus replication in patients with chronic hepatitis B the levels of both TNF-alpha and IL-4 in their blood sera proved to be reliably higher than in patients with hepatitis B virus in the interactive phase.     

Level of serum tumor necrosis factor-alpha and the degree of liver fibrosis in children with chronic viral hepatitis B,C and B+C,treated with interferon-alpha

Children with chronic virus hepatitis B and C, as well as combined chronic virus hepatitis B + C, were found to have a higher level of tumor necrosis factor-alpha (TNF-alpha) in their serum than healthy children. Complete clinical and virological response to treatment with interferon-alpha is accompanied by a decreased inflammation and fibrosis of the liver, as well as by a decreased level of TNF-alpha, in comparison with nonresponsive patients. Positive correlation between the level of TNF-alpha and the degree of liver fibrosis in sick children was noted.     

Schistosomiasis and nutritional myopathy in a Brazilian tapir (Tapirus terrestris)

Gross lesions suggestive of severe hepatoenteropathy and myopathy were noted in a 4.5-yr-old Brazilian tapir (Tapirus terrestris) from a zoo in Michigan (USA). The major microscopic lesions were granulomatous hepatitis and hemorrhagic enteritis associated with non-operculated eggs compatible with those of the Schistosomatidae (Digenea). Skeletal muscle and tongue contained foci of severe acute myodegeneration and necrosis. The hepatic vitamin E value of 1.3 ppm dry weight was considered critically low.     

Serum zinc as a factor predicting response to interferon-alpha2b therapy in children with chronic hepatitis B

Although it has been unclear why more than 50% of children with chronic hepatitis B virus infection do not respond to interferon therapy, in some instances resistance to interferon probably is caused by an inability to stimulate appropriately cellular immune responses to hepatitis B virus. It is known that immune integrity is tightly linked to zinc status. We examined the relationship between serum zinc levels and response to interferon (INF)-α therapy in children with chronic hepatitis B. Twenty-five children with chronic hepatitis B infection were injected with 5 × 10⁶ units/m² recombinant IFN-α 2b subcutaneously three times weekly for 9 mo. Children were followed for at least 9 mo after the end of therapy. Sustained response was obtained in eight (32%) patients. Although initial serum zinc and alanine aminotransferase levels were significantly higher; initial hepatitis B Virus (HBV)-DNA values, hepatic activity index, periportal necrosis, and fibrosis scores were significantly lower in sustained responders than in nonresponders. Mean baseline serum zinc, alanine aminotransferase and HBV-DNA values, histologic activity index, periportal necrosis, and fibrosis scores were predictive of response to IFN-α 2b therapy. These findings suggest that serum zinc levels might be used as a factor predicting response to interferon-α 2b therapy, and so may help in identifying those children with a better chance of response.     

Hemorrhagic enteritis in captive American kestrels (Falco sparverius)

Hemorrhagic enteritis and hepatitis of suspected adenovirus etiology were the apparent cause of death of nine captive American kestrels. Cloacal hemorrhage was the only prominent gross lesion: disseminated hepatocellular necrosis, and intranuclear inclusion bodies were evident microscopically. Electron microscopy revealed numerous adenovirus-like particles associated with the hepatic lesions. Attempts to serologically identify the agent were unsuccessful.     

应用酶联免疫吸附试验检测不同类型乙型肝炎中激活补体类HBsAg循环免疫复合物

本文以抗人C_(?)的羊IgG为包被抗体,以HRP-HBs抗体为指示抗体,建立了可检测激活补体类HBsAg循环免疫复合物(HBsAg/C3-CIC)的C_3捕捉法酶联免疫吸附试验。检测了236例六种类型临床诊断为乙型肝炎的病人血清标本,其阳性率分别为:无症状携带者(ASC)12.9％(4/31),急性肝炎(AH)36.7％(22/60),慢性迁延性肝炎(CPH)33.3％(7/21),慢性活动性肝炎(CAH)59.6％(34/57),重型肝炎(SH)77.8％(14/18),肝炎后肝硬化(PLC)67.3％(33/49),阳性率与肝损严重程度明显相关(P<0.01)。认为HBs-Ag/C3-CIC可能在乙型肝炎病毒引起的慢性活动性肝炎、重型肝炎和肝炎后肝硬化的发病过程中起重要作用,并可作为乙型肝炎的诊断、临床分型和预后判断的指标之一。     

Apoptosis participates to liver damage in HSV-induced fulminant hepatitis

Background: HSV fulminant hepatitis is a rare pathology. Rapid hepatic failure, as a consequence of extended liver damage, has generally been attributed to necrosis. As apoptosis can constitute another way for hepatocytes to die, we decided to investigate whether programmed cell death took place during HSV fulminant hepatitis. Methods: Liver sections were obtained from two cases of fulminant herpetic hepatitis as well as from hepatitis B virus and Rickettsia-infected livers. Herpes simplex virus infection was confirmed using in situ hybridization. Apoptosis was assessed by histopathological examination, p53, activated-caspase 3 and Fas immunohistochemistry and TUNEL labeling. Results: We report that the number of cells expressing activated-caspase 3 was largely increased in fulminant herpes simplex virus hepatitis, when compared to livers chronically infected by hepatitis B virus or from a Rickettsial acute hepatitis. Apoptosis of hepatocytes was confirmed by a positive double-staining for activated-caspase 3 and hepatocytes. Finally, the apoptotic process has progressed beyond the step of nuclear DNA cleavage as demonstrated by TUNEL labeling. Conclusion: These data as a whole show that apoptosis is responsible, at least partially, for liver damage during HSV fulminant hepatitis.     

Detection of hepatitis B virus antigens in paraffin-embedded liver specimens from the Amazon region, Brazil

Hepatic viscerotomy of paraffin-preserved old specimens, collected in the period from 1934 to 1967, were analyzed by immunohistochemical assays to detect hepatitis B, hepatitis D, dengue and yellow fever virus antigens. The material belongs to the Yellow Fever Collection, Department of Pathology, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil and the cases were diagnosed at that time according to clinical aspects and histopathological findings reporting viral hepatitis, yellow fever, focal necrosis and hepatic atrophy. From the 79 specimens, 69 were collected at the Labrea Region and the other 10 in difFerent other localities in the Amazon Region. The five micra thick histological slices were analyzed for the presence of hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) by immunoperoxidase technique. An immunofluorescence assay was applied to the detection of hepatitis D, yellow fever and dengue virus antigens. Nine (11.4%) histological samples were HBsAg reactive and 5 (6.3%) were HBcAg reactive. The oldest reactive sample was from 1934. Viral antigens related to the other pathologies were not detected in this study. Our results confirm that the methodology described may be used to elucidate the aetiology of hepatitis diseases even after a long time of conservation of the specimens.     

Neuroimmunomodulation in human autoimmune liver disease

Bidirectional interaction between immune and nervous systems is considered an important biological process in health and disease. However, little is known about the mechanisms involved in their interaction in the human liver. This study examines the distribution of intrahepatic NPY, SP immunoreactive (IR) nerve fibers and their antomical relationship with immunocells containing tumor necrosis factor-α (TNF-α) and nuclear factor κB (NF-κB) in patients with autoimmune hepatitis. Liver specimens were obtained from control liver and autoimmune hepatitis patients. The immunoreactivity was determined by immunohisto- and immunocytochemistry and confocal laser microscopy. In hepatitis, the number of NPY-IR and SP-IR nerve fibers increased significantly. These IR nerve fibers were in very close contact with the lymphocytes. In healthy controls, no NPY-IR, SP-IR or NF-κB IR lymphocytes and only a few TNF-α positive cells, were observed. In hepatitis, some of the lymphocytes showed immunoreactivity for SP and NPY in the portal area. Fluorescent double-labeled immunostaining revealed that in these cells NPY did not colocalize with TNF-α or NF-κB. However, some of the SP fluorescence-positive immune cells exhibited immunostaining for p65 of NF-κB, where their labeling was detected in the nuclei. Under the electronmicroscope, these cells could be identified (lymphocytes, plasmacells and mast cells). The gap between the IR nerve fibers and immunocells was 1 μm or even less. Overexpression of SP in lymphocytes may amplify local inflammation, while NPY may contribute to liver homeostasis in hepatitis. Neural immunomodulation (SP antagonists and NPY) might be a novel therapeutic concept in the management of liver inflammation.     

Hepatitis B X protein upregulates decoy receptor 3 expression via the PI3K/NF-κB pathway

Chronic hepatitis B (CHB) is associated with the development of hepatocellular carcinoma (HCC). Decoy receptor 3 (DcR3) is a tumor necrosis factor receptor that promotes tumor cell survival by inhibiting apoptosis and interfering with immune surveillance. Previous studies showed that DcR3 was overexpressed in HCC cells and that short hairpin RNA (shDcR3) sensitizes TRAIL-resistant HCC cells. However, the expression of DcR3 during hepatitis B virus (HBV) infection has not been investigated. Here, we demonstrated that DcR3 was overexpressed in CHB patients and that DcR3 upregulation was positively correlated with the HBV DNA load and liver injury (determined by histological activity index, serum alanine aminotransferase level, and aspartate aminotransferase level). We found that hepatitis B virus X protein (HBx) upregulated DcR3 expression in a dose-dependent manner, but this increase was blocked by NF-κB inhibitors. HBx also induced the activation of NF-κB, and the NF-κB subunits p65 and p50 upregulated DcR3 by directly binding to the DcR3 promoters. Inhibition of PI3K significantly downregulated DcR3 and inhibited the binding of NF-κB to the DcR3 promoters. Our results demonstrate that the HBx induced DcR3 expression via the PI3K/NF-κB pathway; this process may contribute to the development of HBV-mediated HCC.     

Plasmapheresis in the treatment of hepatic coma]

Fourteen patients, including 6 with viral hepatitis B and 8 with liver cirrhosis were treated with plasmapheresis for hepatic coma. Altogether 29 plasmaphereses were carried out. Complete recovery was achieved in one patient with viral hepatitis B and in 3 patients with liver cirrhosis. Plasmapheresis should be performed in patients with severe lesions to the liver. Classification of patients to the treatment should include clinical examination, biochemical and enzymatic tests, and evaluation of liver reserve with isotope hepatography. In case of the acute poisoning with hepatotoxic agents indications to plasmapheresis should be evaluated from the toxicologic point of view.     

Hepatitis Viruses and Human Hepatocellular Carcinoma

Two hepatotropic viruses, hepatitis B and C viruses, are known to cause hepatocellular carcinoma in humans. Hepatocarcinogenesis is a complex, stepwise process that evolves over several to many years and precisely how hepatitis viruses contribute to malignant transformation of hepatocytes is uncertain. Hepatitis B vrus is integrated into cellular DNA in the great majority of hepatitis B virus-related hepatocellular carcinomas, whereas replicative intermediates of hepatitis C virus do not insert into chromosomal DNA, making it likely that different pathogenetic mechanisms operate with the two viruses. Indeed, evidence is mounting that both direct and indirect carcinogenic mechanisms, and often the two together, are involved in virus-induced hepatocellular carcinoma. In addition, evidence is now available that hepatitis B and C viruses interact synergistically in the pathogenesis of hepatocellular carcinoma. Animal models, — other members of the Hepadnaviridae family that cause tumors in their respecitve animal hosts, and transgenic mice into which the sequences of hepatitis B virus DNA have been inserted — are proving useful in elucidating putative mechanisms of hepatitis B virus-related hepatocarcinogenesis. Whatever the genesis of hepatitis virus-induced hepatocellular carcinoma, it is clear that hepatitis viruses do not act alone but in conjunction with other environmental carcinogens and a number of host factors.