bluuebunny/crossref_metadata_2025 huggingface dataset:
Recent Portal or Mesenteric Venous Thrombosis: Increased Recognition and Frequent Recanalization on Anticoagulant Therapy
Authors: Condat Bertrand , Pessione Fabienne , Denninger Marie Helene , Hillaire Sophie , Valla Dominique
Published: March 2004

Characteristics and outcomes of recent portal or mesenteric venous thrombosis are ill-known. We intended to compare these features with those of patients with portal cavernoma, and also to assess the incidence of recanalization of recent thrombosis on anticoagulation therapy. All patients seen between 1983 and 1999 were enrolled into this retrospective study if recent portal or mesenteric venous thrombosis or portal cavernoma had been documented, and if cancer of the liver, pancreas, or bile duct, intrahepatic block including cirrhosis, and obstruction of the hepatic veins had been ruled out. The proportion of recent thrombosis was 7% in patients seen before 1990 and 56% after 1994 (P< .05). Patients with recent thrombosis (n = 33) or cavernoma (n = 108) did not differ with regard to age, sex ratio, or prevalence of prothrombotic states and of previous thrombotic events. In patients with recent thrombosis, septic pylephlebitis was more common and the incidence of gastrointestinal bleeding was lower (2.4 vs. 12.7/100 patient-years). Recanalization occurred in 25 of 27 patients given anticoagulation and 0 of 2 patients not given anticoagulation. The probability of recanalization was related to the extent of thrombosis (P= .003). In conclusion, mesenteric or portal venous thrombosis is increasingly recognized at an early stage. The features differentiating recent thrombosis and cavernoma are related to silent onset precluding early recognition and therapy in the latter. Frequent association with prothrombotic states and frequent recanalization on anticoagulation support the recommendation of early anticoagulation therapy in all patients with recent portal vein thrombosis.
Multicenter Randomized Controlled Trial of Terlipressin Versus Sclerotherapy in the Treatment of Acute Variceal Bleeding: The TEST Study
Authors: Escorsell Àngels , Del Arbol Luis Ruiz , Planas Ramon , Albillos Agustín , Bañares Rafael , Calès Paul , Pateron Dominique , Bernard Brigitte , Vinel Jean-Pierre , Bosch Jaume
Published: March 2004

Failure to control bleeding and early rebleeding account for the high mortality associated with variceal hemorrhage in cirrhosis. We compared endoscopic sclerotherapy to terlipressin, a drug that effectively controls acute bleeding while reducing in-hospital mortality. This multicenter randomized controlled trial included 219 cirrhotic patients admitted for endoscopy-proven acute variceal bleeding and randomized to receive repeated injections of terlipressin during 6 days (n = 105) or emergency sclerotherapy (n = 114). Success was defined as obtaining control of bleeding (24-hour bleeding-free period during the first 48 hours) and lack of early rebleeding (any further bleeding from initial control to 5 days later) and survival during the study. Both groups were similar at inclusion. Failure rate for terlipressin was 33% and 32% for sclerotherapy (not significant [NS]). Early rebleeding was responsible for 43% and 44% of failures, respectively. This high efficacy was observed in both Child-Pugh class A + B and Child-Pugh class C patients. Both treatments were similar regarding transfusion requirements, in-hospital stay, and 6-week mortality (26 vs. 19 patients). Side effects appeared in 20% of patients receiving terlipressin and in 30% of those on sclerotherapy (P = .06); being serious in 4% and 7%, respectively (NS). In conclusion, terlipressin and sclerotherapy are equally highly effective therapies achieving the initial control of variceal bleeding and preventing early rebleeding. Both treatments are safe, but terlipressin is better tolerated. Therefore, terlipressin may represent a first-line treatment in acute variceal bleeding until the administration of elective therapy, especially in hospitals where a skilled endoscopist is not available 24 hours a day.
Clearance of the original hepatitis B virus YMDD-motif mutants with emergence of distinct lamivudine-resistant mutants during prolonged lamivudine therapy
Authors: Yeh Chau-Ting , Chien Rong-Nan , Chu Chia-Ming , Liaw Yun-Fan
Published: March 2004

Tyrosine-methionine-aspartate-aspartate (YMDD)-motif mutants may emerge and elicit immune clearance during prolonged lamivudine treatment. The aim of this study was to investigate the virological events following development of the original mutants. Twenty-three patients who developed YMDD-motif mutants during the Asian lamivudine trial were included. Serial serum samples from these patients were subjected to sequence analysis to identify new mutants. Site-directed mutagenesis experiments were performed to investigate whether the new mutations were responsible for lamivudine resistance. Of the 23 patients included, 13 harbored either one or a mixture of the two common YMDD-motif mutants (methionine 552-to-isoleucine [M552I] and leucine 528-to-methionine/methionine 552-to-valine [L528M/M552V]) throughout the course, whereas in the remaining 10 patients, distinct mutants became dominant over the original mutants to cause continuing chronic hepatitis. Of them, 3 developed an alanine 529-to-threonine (A529T) mutant, 6 developed a leucine 528-to-methionine/methionine 552-to-isoleucine (L528M/M552I) mutant, and 1 developed these two mutants sequentially. Site-directed mutagenesis experiments confirmed that the aforementioned mutations were responsible for the resistance to lamivudine in vitro. The nucleotide substitution in the A529T mutant concomitantly generated a stop codon at the surface gene, leading to impaired secretion of HBsAg. Strikingly, the replication of this mutant was lamivudine dependent. These results suggested that distinct lamivudine-resistant mutants could emerge and replace the original YMDD-motif mutants as the cause of continuing chronic hepatitis during prolonged lamivudine therapy.
Hepatitis C virus core protein induces apoptosis and impairs cell-cycle regulation in stably transformed chinese hamster ovary cells
Authors: Honda Masao , Kaneko Shuichi , Shimazaki Takeo , Matsushita Eiki , Kobayashi Kenichi , Ping Li-hua , Zhang Hang-chuen , Lemon Stanley M.
Published: March 2004

Hepatitis C virus (HCV) infection is associated with the development of hepatocellular carcinoma. Several lines of evidence suggest that the core protein of HCV may play a role in the development of this cancer. The authors examined regulation of the cell cycle in stable cell lines derived from Chinese hamster ovary (CHO-K1) cells that constitutively expressed one or more of the structural proteins of HCV. In media containing low concentrations of serum (serum starvation), cell lines expressing the core protein showed a significantly lower population of viable cells than noncore-expressing cells. The low viability of the core-expressing cells was a result of the increased population of cells undergoing apoptosis. Interestingly, the cell cycle analysis revealed that the arresting function at G0 was impaired, and the cell cycle was accelerated in core-expressing cell lines even under serum starvation. Thus, the HCV core protein sensitizes the apoptosis to serum starvation, although it promotes the cell cycle in CHO-K1 cells. To explain these findings, the authors examined the expression of revival apoptosis and cell-cycle-related genes. Expression of the c-mycgenes was significantly induced in core-expressing cells in response to serum starvation. Other apoptosis-inducing genes downstream of c-myc, p53, p21WAF1/CIP1 and Bax were significantly highly induced, although there was no induction of Bcl-2, which prevents apoptosis in core-expressing cells. Thus, the HCV core protein induced apoptosis and impaired the regulation of the cell cycle by activating c-myc expression, whereas the p53 and Bax pathways play a role in the induction of apoptosis.
DNA-based immunization produces Th1 immune responses to hepatitis delta virus in a mouse model
Authors: Huang Yi-Hsiang , Wu Jaw-Ching , Tao Mi-Hua , Syu Wan-Jr , Hsu Sheng-Chieh , Chi Wei-Kuang , Chang Full-Young , Lee Shou-Dong
Published: March 2004

Hepatitis delta virus (HDV) superinfection is one of the major causes of fulminant hepatitis in endemic areas of hepatitis B virus (HBV) infection. Currently, there is no effective treatment or vaccine against HDV superinfection. DNA-based immunization is a promising antiviral strategy to prevent or treat persistent viral infections. In this study, we investigated the immunological effects of DNA vaccines against HDV in BALB/c mice. Plasmid (pD) encoding large hepatitis D antigen (L-HDAg), or plasmid (pS/pD) coexpressing hepatitis B surface antigen (HBsAg) and L-HDAg, were injected into mice intramuscularly. The seroconversion rate, anti-HBs levels, anti-HDV titers, T-cell proliferation responses, and T-helper (Th)-release cytokine profiles were analyzed. Mice immunized with plasmids, pS/pD or pD, produced low, but significant, titers of anti-HDV antibodies. In contrast, pS/pD induced much stronger anti-HBs titers in the immunized animals. Interestingly, splenic lymphocytes derived from pS/pD-inoculated mice demonstrated significant proliferation responses to recombinant HBsAg and HDAg, and resulted in a Th1-like immune response as suggested by the production of interferon gamma (INF-γ) and interleukin-2 (IL-2), but not IL-4. The splenic lymphocyte derived from the pD-inoculated mice showed a similar Th1 response to the stimulation of HDAg, but not to HBsAg. In conclusion, our results suggest that DNA vaccines against HDV can induce significant cellular immune responses with a Th1 preference. HBV and HDV coimmunization can be performed by DNA vaccines. These results are promising for the future development of prophylactic and therapeutic HDV vaccines.
Hepatitis C virus (HCV) infection in a community in the nile delta: Population description and HCV prevalence
Authors: Abdel-Aziz Fatma , Habib Mostafa , Mohamed Mostafa K. , Abdel-Hamid Mohamed , Gamil Foda , Madkour Salah , Mikhail Nabiel N. , Thomas David , Fix Alan D. , Strickland Thomas G. , Anwar Wagida , Sallam Ismail
Published: March 2004

This report describes a cross-sectional survey of the prevalence of antibodies to hepatitis C virus (anti-HCV) in a rural Egyptian community in the Nile Delta. One half of the village households were systematically selected and examined by questionnaire and testing sera for anti-HCV and HCV RNA. Blood samples were obtained from 3,888 (75.4%) of 5,156 residents ≥5 years of age; an additional 111 samples were obtained from children younger than 5 years. Overall, 973 (24.3%) of 3,999 residents were anti-HCV-positive, and the age- and gender-adjusted seroprevalence was 23.7%. Anti-HCV prevalence increased sharply with age, from 9.3% in those 20 years of age and younger to >50% in those older than 35 years. Currently or previously married individuals were more likely to be seropositive than those never married, controlling for age (Mantel-Haenszel risk ratio = 1.8; 95% CI: 1.3, 2.6). Of the 905 anti-HCV-positive samples tested, 65% were also positive for HCV RNA. Active schistosomal infection was not associated with anti-HCV status; however, history of antischistosomal injection therapy (reported by 19% of anti-HCV positives) was a risk for anti-HCV (age-adjusted risk ratio = 1.3; 95% CI: 1.2, 1.5). This study, the largest community-based survey to date, supports earlier reports of high levels of anti-HCV among adults in rural areas of Egypt, although many of those who are seropositive will not have active liver disease. The large reservoir of HCV infection in the community provides an opportunity to investigate risk factors for transmission, the natural history of infection and effectiveness of preventive methodologies, and raises concern about the prospect of an increasing incidence of chronic liver disease in the coming decades.
Reversion of hepatobiliary alterations by bone marrow transplantation in a murine model of erythropoietic protoporphyria
Authors: Fontanellas Antonio , Mazurier Frèdèric , Landry Marc , Taine Laurence , Morel Carine , Larou Monique , Daniel Jean-Yves , Montagutelli Xavier , de Salamanca Rafael Enriquez , de Verneuil Hubert
Published: March 2004

Erythropoietic protoporphyria (EPP) is characterized clinically by cutaneous photosensitivity and biochemically by the accumulation of excessive amounts of protoporphyrin in erythrocytes, plasma, feces, and other tissues, such as the liver. The condition is inherited as an autosomal dominant or recessive trait, with a deficiency of ferrochelatase activity. A major concern in EPP patients is the development of cholestasis with accumulation of protoporphyrin in hepatobiliary structures and progressive cellular damage, which can rapidly lead to fatal hepatic failure. The availability of a mouse model for the disease, the Fechm1Pas/Fechm1Pasmutant mouse, allowed us to test a cellular therapy protocol to correct the porphyric phenotype. When Fech/Fech mice received bone marrow cells from normal animals, the accumulation of protoporphyrin in red blood cells and plasma was reduced 10-fold but still remained 2.5 times above normal levels. Interestingly, in very young animals, bone marrow transplantation can prevent hepatobiliary complications as well as hepatocyte alterations and partially reverse protoporphyrin accumulation in the liver. Bone marrow transplantation may be an option for EPP patients who are at risk of developing hepatic complications.
Detection of hepatitis C virus replication by In situ hybridization in epithelial cells of anti-hepatitis C virus-positive patients with and without oral lichen planus
Authors: Arrieta Juan Jos , Rodriguez-Iñigo Elena , Casqueiro Mercedes , Bartolomé Javier , Manzarbeitia Felix , Herrero Montserrat , Pardo Margarita , Carreño Vicente
Published: March 2004

Epidemiological studies have demonstrated that there is a correlation between oral lichen planus and chronic hepatitis C virus (HCV) infection. HCV RNA has been recently detected in epithelial cells from oral lichen planus lesions by reverse-transcription polymerase chain reaction (RT-PCR). However, this technique does not discriminate which types of cells are infected by the virus or if the viral RNA is present in the serum that contaminates the biopsy. Morphological evidence of viral replication in cells from these lesions is needed to establish a role for HCV in oral lichen planus. Consequently, we have analyzed the presence of positive and negative HCV-RNA strands in oral mucosa biopsies from 23 patients (14 anti-HCV-positive) diagnosed as having oral lichen planus and from 5 patients with chronic hepatitis C without oral lichen planus. Positive and negative HCV-RNA strands were detected in epithelial cells of the mucosa biopsies from all anti-HCV-positive patients independently of whether or not they had oral lichen planus, but in none of the anti-HCV-negative cases. The percentage of stained cells ranged from 4.4% to 14.3%. These percentages do not correlate with the serum viremia levels or the intensity of the cellular infiltrate in patients with oral lichen planus. In conclusion, we have shown that HCV replicates in epithelial cells of patients with and without oral lichen planus. The pathological consequences of this finding remain to be elucidated.
Molecular analysis of hepatitis B virus DNA in serum and peripheral blood mononuclear cells from hepatitis B surface antigen-negative cases
Authors: Cabrerizo María , Bartolomé Javier , Caramelo Carlos , Barril Guillermina , Carreño Vicente
Published: March 2004

We have analyzed the molecular bases of the persistence of hepatitis B virus (HBV) DNA in serum and peripheral blood mononuclear cells (PBMC) in the absence of detectable hepatitis B surface antigen (HBsAg) in hemodialysis patients and dialysis-unit staff members who had suffered acute hepatitis B that resolved previously. HBV DNA was found in both compartments by polymerase chain reaction (PCR) using primers of the pre-S/S region. Viral DNA was transcriptionally active in PBMC, because the covalently closed circular (ccc) HBV DNA, the template for the viral RNA transcription, was detected in 47% of the samples. Furthermore, all PBMC had HBV RNA. HBsAg-negative cases had statistically lower levels of HBV DNA in serum and PBMC than a control group of chronic HBsAg carriers. We have also studied the presence of immune complexes and the existence of mutations in the pre-S/S gene to explain the lack of detection of HBsAg in these cases. No serum HBsAg/hepatitis B surface antigen antibody (anti-HBs) immune complexes or mutations in the “a” determinant of the S gene were found. However, we have observed that all HBsAg-negative cases were infected by a mixture of the wild-type virus and a deletion mutant in the pre-S1 region. This deletion (amino acids 58-118) affects the S gene promoter, and previousin vitrostudies have shown that it produces a reduction of the HBsAg synthesis. In conclusion, this work shows that the lack of detection of HBsAg in the presence of low viral levels of replication may be caused by the existence of viral genomes harboring deletions in the pre-S1 region that affect the S promoter.
Increased hepatocyte turnover and inhibition of woodchuck hepatitis B virus replication by adefovir In vitro do not lead to reduction of the closed circular DNA
Authors: Dandri Maura , Burda Martin R. , Will Hans , Petersen Joerg
Published: March 2004

The aim of this study was to evaluate the inhibitory effect of the nucleotide analogue adefovir on woodchuck hepatitis B virus (WHV) replication and, in particular, to determine whether the pool of covalently closed circular DNA (cccDNA) could be reduced by adefovir treatment in primary cultures of woodchuck hepatocytes isolated from a chronic carrier. Strong reduction of WHV-DNA synthesis (90%) and secretion (up to 98%) was observed with all 3 doses of adefovir used (1, 10, and 100 μmol/L), whereas in the absence of the drug, high amounts of viral particles were continuously secreted in the culture medium until the end of the study (27 days). Secretion of envelope proteins and viral RNA levels remained constant both in the adefovir-treated and -untreated cultures for the entire course of the study. Intracellular core protein levels declined by approximately 50% in all the cultures, independent of adefovir treatment. There was no indication of cccDNA loss in the adefovir-treated hepatocyte cultures even when cell turnover was induced for 14 days by the addition of epidermal growth factor (EGF) to the culture medium. Our data show that adefovir has a very strong inhibitory effect on WHV-DNA synthesis in chronically infected primary hepatocyte cultures and indicate that cccDNA is a very stable molecule that appears to be efficiently transmitted to the dividing hepatocytes.
Contribution of adenosine A2 receptors and cyclic adenosine monophosphate to protective ischemic preconditioning of sinusoidal endothelial cells against storage/reperfusion injury in rat livers
Authors: Arai Masahiro , Thurman Ronald G. , Lemasters John J.
Published: March 2004

A brief period of liver ischemia decreases sinusoidal endothelial cell killing after cold liver storage and improves graft survival after liver transplantation, a phenomenon called ischemic preconditioning. In this study, we investigated the mechanism of sinusoidal endothelial cell protection after ischemic preconditioning. Livers were preconditioned by 5 minutes of ischemia and 5 minutes of reperfusion. Subsequently, livers were stored for 30 hours in cold University of Wisconsin (UW) solution and reperfused briefly with physiological buffer containing Trypan blue. Ischemic preconditioning decreased sinusoidal endothelial cell killing after storage/reperfusion, as assessed by Trypan blue staining of nonparenchymal cells. Adenosine A2 receptor blockade prevented the protective effect of ischemic preconditioning. By contrast, adenosine A1 receptor blockade did not prevent protective ischemic preconditioning. Other rat livers were treated with adenosine A1 and A2 receptor agonists or dibutyryl-cyclic adenosine monophosphate (DB-cAMP) before storage. The adenosine A2 receptor agonist, CGS-21680, and DB-cAMP decreased sinusoidal endothelial cell killing to the same extent as ischemic preconditioning, but the adenosine A1 receptor agonist, 2-chloro-N
6-cyclopentyladenosine (CCPA), had no effect. The adenosine A2 agonist and prostaglandin E2, another agent that preconditions sinusoidal endothelial cells against storage/reperfusion injury, but not the adenosine A1 agonist, increased cAMP levels in cultured sinusoidal endothelial cells. In conclusion, an adenosine A2 receptor pathway coupled to increased cAMP mediates sinusoidal endothelial cell protection by ischemic preconditioning.
Cytochrome P450-generated reactive metabolites cause mitochondrial permeability transition, caspase activation, and apoptosis in rat hepatocytes
Authors: Haouzi Delphine , Lekéhal Mounia , Moreau Alain , Moulis Claude , Feldmann Gérard , Robin Marie-Anne , Lettéron Philippe , Fau Daniel , Pessayre Dominique
Published: March 2004

Although cytochrome P-450 (CYP)-generated reactive metabolites can cause hepatocyte apoptosis, the mechanism of this effect is incompletely understood. In the present study, we assessed the hepatotoxicity of skullcap, a diterpenoid-containing herbal remedy. Male rat hepatocytes were incubated for 2 hours with skullcap diterpenoids (100 μg/mL). This treatment decreased cell glutathione and protein thiols and increased cell [Ca2+]. This activated Ca2+-dependent tissue transglutaminase, forming a cross-linked protein scaffold, and also opened the mitochondrial permeability transition pore, causing outer mitochondrial membrane rupture, increased cytosolic cytochrome c, activation of procaspase 3, internucleosomal DNA fragmentation, and ultrastructural features of apoptosis. Cell death was increased by a CYP3A inducer (dexamethasone) or a sulfur amino acid-deficient diet increasing glutathione depletion. In contrast, cell death was prevented by decreasing CYP3A activity (with troleandomycin), preventing glutathione depletion (with cysteine or cystine), blocking Ca2+-modulated events (with calmidazolium), preventing mitochondrial permeability transition (with cyclosporin A), or inhibiting caspase 3 (with acetyl-Asp-G u-Va-Asp-a dehyde). Both calmidazolium and cyclosporin A also prevented the increase in cytosolic cytochrome c and procaspase 3 activation. In conclusion, CYP3A activates skullcap diterpenoids into reactive metabolites that deplete cellular thiols and increase cell [Ca2+]. This activates Ca2+-dependent transglutaminase and also opens the mitochondrial permeability transition pore, causing outer mitochondrial membrane rupture, cytochrome c release, and caspase activation. Preventing mitochondrial permeability transition pore opening and/or caspase activity blocks apoptosis, showing the fundamental role of these final events in metabolite-mediated hepatotoxicity.
Liver transplantation for autoimmune hepatitis: A long-term pathologic study
Authors: Ayata Gamze , Gordon Fredric D. , Lewis David W. , Pomfret Elizabeth , Pomposelli James J. , Jenkins Roger L. , Khettry Urmila
Published: March 2004

Autoimmune hepatitis (AIH) after liver transplantation (LT) may recur and is difficult to diagnose. Our aims were to define the histopathology of and factors related to AIH recurrence. Fourteen of 475 patients received LT for AIH; 2 died perioperatively. Liver specimens (native and post-LT biopsies) from 12 other patients were reviewed and correlated with pre- and post-LT clinical course and outcome. Recurrent AIH was seen in 5 of 12 patients, 35 to 280 days post-LT as lobular hepatitis with acidophil bodies and lymphoplasmacytic infiltrate. Portal/interface hepatitis was seen with disease progression and 2 of 5 patients developed cirrhosis. Of 7 nonrecurrent patients, 1 had acquired hepatitis C with lobular/portal hepatitis and none developed cirrhosis. Histology suggestive of overlap syndrome was seen in 3 of 12 native livers with no effect on post-LT course or pathology. High-grade necroinflammation was present in native livers at LT in 5 of 5 cases with recurrent AIH and in 1 of 7 without recurrence (P < .01). Pre-LT disease duration, donor/recipient gender distribution, HLA studies, and rejection episodes did not correlate with AIH recurrence. We conclude that (1) recurrent AIH is not uncommon and was seen in 42% of patients with lymphoplasmacytic lobular, portal, and interface hepatitis; (2) acidophil bodies with lymphoplasmacytic cells are seen in early recurrent AIH; (3) recurrent AIH appears at variable time periods post-LT, and the progression is slow; and (4) high-grade inflammation in native liver at LT is a strong predictor of recurrent AIH.
Liver from bone marrow in humans
Authors: Theise Neil D. , Nimmakayalu Manjunath , Gardner Rebekah , Illei Peter B. , Morgan Glyn , Teperman Lewis , Henegariu Octavian , Krause Diane S.
Published: March 2004

It has been shown in animal models that hepatocytes and cholangiocytes can derive from bone marrow cells. We have investigated whether such a process occurs in humans. Archival autopsy and biopsy liver specimens were obtained from 2 female recipients of therapeutic bone marrow transplantations with male donors and from 4 male recipients of orthotopic liver transplantations from female donors. Immunohistochemical staining with monoclonal antibody CAM5.2, specific for cytokeratins 8, 18, and 19, gave typical strong staining of hepatocytes, cholangiocytes, and ductular reactions in all tissues, to the exclusion of all nonepithelial cells. Slides were systematically photographed and then restained by fluorescence in situ hybridization (FISH) for X and Y chromosomes. Using morphologic criteria, field-by-field comparison of the fluorescent images with the prior photomicrographs, and persistence of the diaminiobenzidene (DAB) stain through the FISH protease digestion, Y-positive hepatocytes and cholangiocytes could be identified in male control liver tissue and in all study specimens. Cell counts were adjusted based on the number of Y-positive cells in the male control liver to correct for partial sampling of nuclei in the 3-micron thin tissue sections. Adjusted Y-positive hepatocyte and cholangiocyte engraftment ranged from 4% to 43% and from 4% to 38%, respectively, in study specimens, with the peak values being found in a case of fibrosing cholestatic recurrent hepatitis C in one of the liver transplant recipients. We therefore show that in humans, hepatocytes and cholangiocytes can be derived from extrahepatic circulating stem cells, probably of bone marrow origin, and such “transdifferentiation” can replenish large numbers of hepatic parenchymal cells.
Common and epithelioid variants of hepatic angiomyolipoma exhibit clonal growth and share a distinctive immunophenotype
Authors: Flemming Peer , Lehmann Ulrich , Becker Thomas , Klempnauer Jürgen , Kreipe Hans
Published: March 2004

Angiomyolipoma represents a rare liver tumor of uncertain histogenesis that is commonly considered a hamartoma. A series of 12 hepatic angiomyolipomas, including 3 samples of the epithelioid subtype, was analyzed for clonality using the human androgen receptor gene locus (HUMARA). Four of 6 informative cases revealed monoclonality. The polyclonal pattern in the 2 remaining cases was most probably caused by excessive infiltration of inflammatory cells. Monoclonality with an identical X-chromosomal inactivation pattern in all nodules was found in a multifocal recurrent tumor indicating a metastatic process. Despite the morphologic heterogeneity, all tumors displayed an identical immunohistochemical labeling pattern. It is concluded that different subtypes of hepatic angiomyolipoma exhibit a monoclonal and hence probably neoplastic growth and share an identical immunophenotype suitable for their identification even in small biopsy specimens. The epithelioid subtype may give rise to intrahepatic metastasis.
Combination therapy with lamivudine and famciclovir for chronic hepatitis B-infected Chinese patients: A viral dynamics study
Authors: Lau George Ka , Tsiang Manuel , Hou Jinlin , Yuen Siu-tsan , Carman William F. , Zhang Liang , Gibbs Craig S. , Lam Shiu-kum
Published: March 2004

In vitrostudies have shown that lamivudine and penciclovir (the active metabolite of famciclovir) act synergistically to inhibit hepatitis B virus (HBV) replication. We compared the effectiveness of HBV viral suppression by lamivudine monotherapy versus lamivudine plus famciclovir combination therapy in Chinese patients with chronic HBV infection. Twenty-one Chinese hepatitis B e antigen (HBeAg)-positive patients, with detectable HBV DNA (Digene Hybrid Capture II), were randomized to receive either lamivudine 150 mg/d orally (group 1, 9 patients) or lamivudine 150 mg/d plus famciclovir 500 mg 3 times a day orally (group 2, 12 patients) for 12 weeks, with a follow-up period of at least 16 weeks. Serial serum HBV-DNA levels were determined and a mathematical model with provision for incomplete inhibition of virus production during therapy was applied to analyze the dynamics of viral clearance. The mean antiviral efficacy was significantly greater in group 2 than in group 1 (0.988 ± 0.012 vs. 0.94 ± 0.03,P= .0012). HBV DNA returned to pretreatment level within 16 weeks after the end of initial treatment in 4 patients (66.7%) in group 1 and none in group 2 (P= .08), who remained HBeAg positive and received no further treatment after week 12. Hence, in Chinese chronic HBeAg-positive patients, combination therapy using lamivudine and famciclovir was superior to lamivudine monotherapy in inhibiting HBV replication. Further studies of longer duration are needed to define whether combination therapy will increase the HBeAg seroconversion rate and decrease the rate of emergence of lamivudine-resistant variants.
Bax-mediated apoptosis in the livers of rats after partial hepatectomy in the retrorsine model of hepatocellular injury
Authors: Gordon Gavin J. , Coleman William B. , Grisham Joe W.
Published: March 2004

Retrorsine is a member of the pyrrolizidine alkaloid family of compounds whose toxic effects on the liver include a long-lasting inhibition of the proliferative capacity of hepatocytes. Despite the retrorsine-induced blockade of hepatocyte proliferation, retrorsine-exposed rats are able to reconstitute completely their liver mass after surgical partial hepatectomy (PH) via the sustained proliferation of a population of small, incompletely differentiated hepatocyte-like progenitor cells (SHPCs). The extensive proliferation of SHPCs in retrorsine-injured livers is accompanied by the progressive loss of irreversibly injured megalocytes. To study the mechanism by which retrorsine-damaged hepatocytes are removed after PH, we performed TUNEL analysis to establish apoptotic indices for hepatocytes in the livers of retrorsine-exposed and control rats up to 14 days post-PH. Apoptotic indices are highest (approximately 6.0%) in the livers of retrorsine-exposed rats at 1 day post-PH, gradually declining thereafter, yet remaining significantly elevated (approximately 1%) over control rats (<0.1%) at 14 days post-PH (P < .05). After PH, levels of the proapoptotic protein Bax are increased in livers from retrorsine-exposed rats relative to the levels observed in control livers. Similarly, levels of the antiapoptotic protein Bcl-xL are significantly decreased (P < .05) compared with controls at t = 0 resulting in an increased (approximately 3.5-fold) Bax/Bcl-x protein ratio that is significantly elevated (P < .05) compared with controls. Finally, increased levels of Bax protein are localized to the mitochondria of retrorsine-exposed rat livers after PH during the same time that cytochrome c is released. These observations combine to suggest that retrorsine-injured hepatocytes are removed after PH via apoptotic pathways dependent on relative levels and localization of Bax and Bcl-xL protein.
Effects of carcinogen-induced transcription factors on the activation of hepatitis B virus expression in human hepatoblastoma HepG2 cells and its implication on hepatocellular carcinomas
Authors: Banerjee Ranjit , Caruccio Lorraine , Zhang Yu Jing , McKercher Scott , Santella Regina M.
Published: March 2004

To elucidate the molecular mechanisms involved in the action of common carcinogens, which can act as important cofactors in modulating hepatitis B virus-mediated hepatocellular carcinogenesis, we have investigated the influence of aflatoxin B1 (AFB), a potent liver carcinogen, as well as benzo[a]pyrene (BP) and 4-aminobiphenyl (4-ABP), carcinogens in cigarette smoke, on the induction of various transcription factors in human hepatoblastoma HepG2 cells. DNA electrophoretic mobility shift assays were performed with nuclear extracts from HepG2 cells treated with 10 μmol/L AFB, 40 μmol/L BP, or 300 μmol/L 4-ABP for 6 and 24 hours. Eight- and 6-fold increases in nuclear transcription factor κB (NF-κB), and 5- and 10-fold increases in activated protein (AP-1) transcription factor were observed with 24 hours AFB and BP treatments, respectively, whereas 4-ABP treatment resulted in an approximately 4-fold induction of both NF-κB and AP-1. Moreover, 4-ABP gave the strongest NF-κB activation in 6 hours of treatment. Four- and 10-fold activation of stress protein was detected by a consensus heat shock factor (HSF) sequence binding probe, with AFB and BP treatments, respectively. DNA adducts were observed by immunoassays in HepG2 cells treated with AFB and BP but not with 4-ABP. Increased human hepatitis B virus (HBV) surface antigen (HBsAg) synthesis was detected in AFB- and BP-treated HepG2 cells following transfection with recircularized HBV DNA. These data suggest that certain carcinogen-induced transcription factors may influence viral carcinogenesis and initiate hepatocellular carcinomas (HCC).
The significance of baseline serum alanine aminotransferase on pretreatment disease characteristics and response to antiviral therapy in chronic hepatitis C
Authors: Gordon Stuart C. , Fang Jane W. , Silverman Ann L. , McHutchison John G. , Albrecht Janice K.
Published: March 2004

We sought to determine whether pretreatment serum alanine aminotransferase (ALT) levels in patients with chronic hepatitis C virus (HCV) correlate with demographic features and other disease characteristics and whether these values influence response to therapy. A total of 1,744 patients with HCV received either interferon alfa-2b and placebo or combination interferon alfa-2b and ribavirin for 24 or 48 weeks. Of these, 105 individuals (6%) had minimally raised serum ALT determinations at entry visit of ≤1.3 × the upper limit of normal (ULN). By analysis of variance both pretreatment histologic activity index (HAI) scores (P < .0001) and fibrosis scores (P = .003) were significantly lower among patients with baseline ALT levels ≤1.3 × ULN. Individuals with lower pretreatment ALT values were younger and weighed less than the ALT >1.3 × ULN cohort. Baseline ALT was not related to gender, race, baseline viral level, or HCV genotype. Using logistic regression analysis, the only demographic feature associated with ALT ≤1.3 × ULN was lower baseline weight and lower baseline HAI score. There was no difference in sustained response between patients with baseline ALT levels ≤1.3 × ULN and those with >1.3 × ULN, in all treatment groups (26 of 105, 24.8% for ALT ≤1.3 × ULN; 440 of 1,639, 26.8% for ALT >1.3 × ULN). We conclude that HCV patients with minimally raised ALT values (≤1.3 × ULN) weigh less, and have lower histologic inflammatory scores than patients with more conventionally elevated ALT levels. Despite these differences, these patients have a similar sustained response to antiviral therapy.
Interferon beta prevents recurrence of hepatocellular carcinoma after complete resection or ablation of the primary tumor—A prospective randomized study of hepatitis C virus-related liver cancer
Authors: Ikeda Kenji , Arase Yasuji , Saitoh Satoshi , Kobayashi Masahiro , Suzuki Yoshiyuki , Suzuki Fumitaka , Tsubota Akihito , Chayama Kazuaki , Murashima Naoya , Kumada Hiromitsu
Published: March 2004

Because hepatocellular carcinoma often recurs after surgical resection or ethanol injection therapy, we conducted a prospective randomized controlled trial of interferon (IFN) in patients with chronic liver disease caused by hepatitis C virus (HCV). Twenty eligible patients with cirrhosis were randomized into two groups: 10 patients treated with 6 million units of natural IFN-β twice a week for 36 months and 10 patients without IFN therapy. One patient within the treatment group discontinued interferon therapy after 19 months of treatment because of a mild degree of retinopathy. None of the patients in either group lost HCV-RNA until the end of the observation. Although 7 (70.0%) of 10 patients in the nontreatment group showed tumor recurrence, only 1 (10.0%) of 10 patients with IFN therapy developed tumor recurrence during a median observation period of 25.0 months. Cumulative recurrence rates of the treated and untreated groups were 0% and 62.5% at the end of the first year, and 0% and 100% at the second year, respectively (log-rank test, P = .0004). In conclusion, intermittent administration of IFN suppressed tumor recurrence after treatment with surgery or ethanol injection in patients with HCV-related chronic liver disease.
Antibodies Against Hepatitis C Virus-Like Particles and Viral Clearance in Acute and Chronic Hepatitis C
Authors: Baumert Thomas F. , Wellnitz Sabine , Aono Shigeaki , Satoi Jujin , Herion David , Gerlach Tilman J. , Pape Gerd R. , Lau Johnson Y.N. , Hoofnagle Jay H. , Blum Hubert E. , Liang Jake T.
Published: March 2004

We recently described the efficient assembly of hepatitis C virus (HCV) structural proteins into HCV-like particles (HCV-LPs) in insect cells. These noninfectious HCV-LPs have similar morphologic and biophysical properties as putative virions isolated from HCV-infected humans and can induce a broadly directed immune response in animal models. The HCV envelope proteins of HCV-LPs are presumably presented in a native, virion-like conformation and may therefore interact with antienvelope antibodies directed against conformational epitopes. In this study, HCV-LPs were used as capture antigens in an enzyme-linked immunosorbent assay (ELISA) to detect and quantify antibodies against HCV structural proteins in patients with acute and chronic hepatitis C. High titers of anti-HCV-LP antibodies were detected in patients chronically infected with HCV genotypes 1 to 6. In contrast to individuals with chronic hepatitis C, patients with acute self-limited hepatitis C displayed only a transient and weak seroreactivity against HCV-LPs. Patients with chronic HCV infection successfully treated with interferon demonstrated a gradual decline of anti-HCV-LP titers during or subsequent to viral clearance. Sustained interferon responders were characterized by significantly higher pretreatment levels of anti-HCV-LP antibodies as compared with nonresponders (P = .0001). In conclusion, HCV infection is associated with limited humoral immunity against the envelope proteins present on the HCV-LPs. An HCV-LP-based ELISA may be a useful diagnostic tool to distinguish acute hepatitis C from chronic HCV infection with exacerbation, and to predict viral clearance in response to interferon.
Regulation of oxysterol 7α-hydroxylase (CYP7B1) in primary cultures of rat hepatocytes
Authors: Pandak William M. , Hylemon Phillip B. , Ren Shunlin , Marques Dalila , Gil Gregorio , Redford Kaye , Mallonee Darrell , Vlahcevic Rano Z.
Published: March 2004

Conversion of cholesterol into 7α-hydroxylated bile acids is a principal pathway of cholesterol disposal. Cholesterol 7α-hydroxylase (CYP7A1) is the initial and rate-determining enzyme in the “classic” pathway of bile acid synthesis. An “alternative” pathway of bile acid synthesis is initiated by sterol 27-hydroxylase (CYP27) with subsequent 7α-hydroxylation of 27-hydroxycholesterol by oxysterol 7α-hydroxylase (CYP7B1). The regulation of CYP7B1, possibly a rate-determining enzyme in the alternative pathway, has not been thoroughly studied. The aims of this study were to (1) study the regulation of liver CYP7B1 by bile acids, cholesterol, adenosine 3', 5'-cyclic monophosphate (cAMP), and phorbol myristate acetate (PMA) in primary rat hepatocytes and (2) determine the effect of CYP7B1 overexpression on rates of bile acid synthesis. The effects of different bile acids (3-150 μmol/L), cAMP (50 μmol/L), PMA (100 nmol/L; protein kinase C stimulator), cholesterol (200 μmol/L), and squalestatin (1 μmol/L; cholesterol synthesis inhibitor) on CYP7B1 expression in primary rat hepatocytes were studied. Taurocholic acid and taurodeoxycholic acid decreased CYP7B1 activity by 45% ± 10% and 36% ± 7%, respectively. Tauroursodeoxycholic acid and taurochenodeoxycholic acid did not alter CYP7B1 activity. Inhibition of cholesterol synthesis with squalestatin decreased CYP7B1 activity by 35%, whereas addition of cholesterol increased activity by 39%. Both PMA and cAMP decreased CYP7B1 activity by 60% and 34%, respectively, in a time-dependent fashion. Changes in CYP7B1 messenger RNA (mRNA) levels correlated with changes in specific activities. Overexpression of CYP7B1 led to a marked increase in CYP7B1 mRNA levels and specific activity but no change in rates of bile acid synthesis. In conclusion, in the rat, CYP7B1 specific activity is highly regulated but does not seem to be rate limiting for bile acid synthesis.
A novel mechanism for mitogenic signaling via pro-transforming growth factor α within hepatocyte nuclei
Authors: Grasl-Kraupp Bettina , Schausberger Elisabeth , Hufnagl Karin , Gerner Christopher , Löw-Baselli Alexandra , Rossmanith Walter , Parzefall Wolfram , Schulte-Hermann Rolf
Published: March 2004

Transforming growth factor (TGF) α, an important mediator of growth stimulation, is known to act via epidermal growth factor receptor (EGF-R) binding in the cell membrane. Here we show by immunohistology, 2-dimensional immunoblotting, and mass spectrometry of nuclear fractions that the pro-protein of wild-type TGF-α occurs in hepatocyte nuclei of human, rat, and mouse liver. Several findings show a close association between nuclear pro-TGF-α and DNA synthesis. (1) The number of pro-TGF-α+ nuclei was low in resting liver and increased dramatically after partial hepatectomy and after application of hepatotoxic chemicals or the primary mitogen cyproterone acetate (CPA); in any case, S phase occurred almost exclusively in pro-TGF-α+ nuclei. The same was found in human cirrhotic liver. (2) In primary culture, 7% of hepatocytes synthesized pro-TGF-α, which then translocated to the nucleus; 70% of these nuclei subsequently entered DNA replication, whereas only 2% of pro-TGF-α− hepatocytes were in S phase. (3) The frequency of hepatocytes coexpressing pro-TGF-α and DNA synthesis was increased by the hepatomitogens CPA or prostaglandin E2 and was decreased by the growth inhibitor TGF-β1. (4) Treatment with mature TGF-α increased DNA synthesis exclusively in pro-TGF-α− hepatocytes, which was abrogated by the EGF-R tyrosine kinase inhibitor tyrphostin A25. In conclusion, TGF-α gene products may exert mitogenic effects in hepatocytes via 2 different signaling mechanisms: (1) the “classic” pathway of mature TGF-α via EGF-R in the membrane and (2) a novel pathway involving the presence of pro-TGF-α in the nucleus.
Proteomic analysis and molecular characterization of tissue ferritin light chain in hepatocellular carcinoma
Authors: Park Kang-Sik , Kim Hoguen , Kim Nam-Gyun , Cho Sang Yun , Choi Kun-Ho , Seong Je Kyung , Paik Young-Ki
Published: March 2004

To investigate a molecular basis for iron depletion in human hepatocellular carcinoma (HCC), 19 cases of HCC were analyzed by two-dimensional electrophoresis (2DE) and matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS). Results were compared with those of paired adjacent nontumorous liver tissues. Comparative analysis of the respective spot patterns in 2DE showed that tissue ferritin light chain (T-FLC), an iron-storage protein, was either severely suppressed or reduced to undetectable levels in HCC, which was further supported by Western blot and immunohistochemical analysis. In contrast, transferrin receptor (TfR) was shown to be overexpressed in the same HCC samples. Interestingly, the relative levels of messenger RNA (mRNA) expression of T-FLC in HCC, which were measured by a real-time quantitative reverse-transcription polymerase chain reaction (PCR), exhibited almost the same levels as those in normal tissues, suggesting that the translational or posttranslational modification of T-FLC may be the cause of T-FLC suppression in HCC. Furthermore, with PCR-based loss of heterozygosity analysis, only 1 of 19 HCCs showed chromosomal deletions at 19q13.3-q13.4 where T-FLC is located, indicating that the suppression of T-FLC is unlikely due to structural genomic changes with HCC. In conclusion, both proteomic and genomic evidence support not only a basis for the suppression of T-FLC in HCC but also provide a new clue to the unresolved question of iron depletion during hepatocarcinogenesis.
Noninvasive gene delivery to the liver by mechanical massage
Authors: Liu Feng , Huang Leaf
Published: March 2004

With the recent completion of the human genome project and the tremendous growth of biotechnology, the desire to extract information concerning gene expression, protein level, subcellular localization, and functionality in the liver will demand the development of efficient gene transfer to this organ with minimal toxicity. In this report, we show that significant gene expression in the liver could be achieved by simple mechanical massage after intravenous injection of naked plasmid DNA into mice. This method is simple, highly reproducible, repeatable, and, more importantly, free of toxicity. Hepatic gene transfer with hepatocyte growth factor (HGF) plasmid DNA prevented endotoxin-induced lethal fulminant hepatic failure, leading to dramatically enhanced survival in mice.
Treatment of hepatocellular carcinoma with radiofrequency ablation: Radiologic-histologic correlation during follow-up periods
Authors: Morimoto Manabu , Sugimori Kazuya , Shirato Kazuhito , Kokawa Atsushi , Tomita Naohiko , Saito Takafumi , Tanaka Noriko , Nozawa Akinori , Hara Masamichi , Sekihara Hisahiko , Shimada Hiroshi , Imada Toshio , Tanaka Katsuaki
Published: March 2004

To determine whether radiographic images after radiofrequency (RF)-induced coagulation necrosis are correlated with the pathologic effects, we evaluated the morphology and histologic characteristics of RF ablation lesions over a 6-month follow-up period and compared the results with those of radiologic studies. Thirty-three hepatocellular carcinoma (HCC) tumors with a maximum diameter of 3 cm or less were treated percutaneously by using RF ablation in 26 patients. Six treated tumors were resected 4 weeks after ablation; the remaining 27 treated tumors underwent a biopsy procedure by using an 18-gauge fine needle 3 days, 4 weeks, and 24 weeks after ablation. The excised or biopsied lesions were examined by using histologic methods; the findings were then compared with those of contrast-enhanced computed tomography (CT). Three days after ablation, a core of hypoattenuation surrounded by an enhanced/hemorrhagic rim was observed on the contrast-enhanced CT images. Hematoxylin-eosin-stained specimens were inconclusive as to whether or not cellular viability remained; however, cell viability as determined by the presence of histochemical (lactate-dehydrogenase, maleate-dehydrogenase, and the reduced form of nicotinamide-adenine dinucleotide phosphate [NADPH]-diaphorase) stains was absent, suggesting 100% cellular destruction in the ablated lesion. Four and 24 weeks after ablation, the sizes of the ablated lesions were progressively smaller on the CT images; the histochemical stains remained superior to the hematoxylin-eosin stains for obtaining a definite diagnosis of cell death. We conclude that irreversible cellular destruction, as determined by the absence of positive histochemical staining patterns, was useful for evaluating the pathologic thermal effect of RF ablation. These pathologic findings can be correlated with those of contrast-enhanced CT.