bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of hepatitis C virus RNA prevalence and surrogate markers of infection among seropositive voluntary blood donors
Authors: Romeo Joseph M. , Ulrich Paul P. , Busch Michael P. , Vyas Girish N.
Published: March 2007

A novel reverse transcription polymerase chain reaction assay has been developed that uses drop-in-drop-out primers for the heminested amplification of hepatitis C virus complementary DNA. This assay has been used for analysis of the prevalence of hepatitis C virus RNA in a set of 53 plasma specimens from blood donations that were repeatedly reactive for hepatitis C virus antibodies with the first-generation enzyme immunoassay. Of 21 specimens that were also reactive for hepatitis C virus antibodies by a four-antigen recombinant immunoblot assay (recombinant immunoblot assay 2), 20 (95%) contained detectable levels of hepatitis C virus RNA. Cryoprecipitate in three specimens reactive in the recombinant immunoblot assay led to an apparent failure of detecting hepatitis C virus RNA, but repeat tests of redissolved cryoprecipitate subsequently revealed hepatitis C virus RNA. Hepatitis C virus RNA was also detected in plasma from 5 of 29 donors nonreactive by recombinant immunoblot assay. However, evidence of viremia in these donors could not be confirmed on follow-up specimens collected more than 1 yr later. Our results demonstrate that the presence of recombinant immunoblot assay reactivity nearly always indicates hepatitis C viremia and suggest that viremia may be transient or fluctuating among some individuals who are nonreactive for hepatitis C virus antibodies by the recombinant immunoblot assay. (Hepatology 1993;17:188-195.)
Renal vasoconstriction in cirrhosis evaluated by duplex doppler ultrasonography
Authors: Sacerdoti David , Bolognesi Massimo , Merkel Carlo , Angeli Paolo , Gatta Angelo
Published: March 2007

Studies of renal perfusion when kidney function tests are still normal could be useful to understand the pathophysiology of functional kidney impairment in cirrhosis; currently, this requires invasive methodology. Duplex Doppler ultrasonography allows noninvasive evaluation of intrarenal arterial resistances. In 19 nonascitic and 35 ascitic cirrhotic patients with normal kidney function (normal serum creatinine and urea levels) and in 17 controls, we measured the intrarenal arterial pulsatility index (Pulsatility index = [Peak systolic velocity - Minimum diastolic velocity]/Mean velocity) and the resistive index (Resistive index = [Peak systolic velocity - Minimum diastolic velocity]/Peak systolic velocity) by duplex Doppler ultrasonography after visualization of interlobar, interlobular or arcuate arteries by color Doppler ultrasonography. The pulsatility index and resistive index (calculated as the mean of three to five consecutive determinations) were significantly higher in cirrhotic patients than in control patients (pulsatility index: 1.16 ± 0.24 vs. 0.78 ± 0.05 [mean ± S.D.], p < 0.001; resistive index: 0.67 ± 0.06 vs. 0.53 ± 0.03, p < 0.001). The pulsatility index and resistive index were significantly higher in nonascitic cirrhotic patients than in control patients, in ascitic patients than in nonascitic patients, in ascitic patients not treated with diuretics than in nonascitic ones and in ascitic patients treated with diuretics than in those not treated. The pulsatility index and resistive index measured before and after treatment with diuretics (7 to 15 days) in seven patients were significantly increased by treatment. The pulsatility index and resistive index were significantly higher in Child-Turcotte-Pugh class B and C patients than in class A patients. The pulsatility index and resistive index inversely correlated with creatinine clearance and directly correlated with heart rate. Thus renal arterial resistance indexes evaluated by duplex Doppler ultrasonography were already increased in the nonascitic phase of cirrhosis and were greater in the ascitic phase, particularly during diuretic treatment, which was also shown to increase renal resistance. This noninvasive method may be applied to pathophysiological and clinical studies of the renal functional impairment of cirrhosis. (Hepatology 1993;17:219-224.)
Interferon suppresses erythromycin metabolism in rats and human subjects
Authors: Craig Philip I. , Tapner Michael , Farrell Geoffrey C.
Published: March 2007

Interferon down-regulates expression of cytochrome P-450 3A in male rats. This study explored the hypothesis that interferon therefore decreases the metabolism of drugs catalyzed by cytochrome P-450 3A. Initial experiments in male rats used microsomal erythromycin N-demethylase activity as a probe for cytochrome P-450 3A catalytic activity. After administration of rat interferon-γ, erythromycin metabolism was impaired (53% of control; p < 0.01). This change correlated with the decline in cytochrome P-450 3A-dependent androstenedione 6β-hydroxylase activity, indicating that the decrease in erythromycin N-demethylase activity could be attributed to interferon-mediated suppression of cytochrome P-450 3A. We then used the [14C]N-methyl erythromycin breath test to assess the activity of hepatic cytochrome P-450 3A in rats and human subjects before and after a single dose of interferon. In rats, rat interferon-γ decreased erythromycin metabolism to 57% of control (p < 0.005). In the human study, six patients with chronic active hepatitis C and four healthy controls were examined 20 to 26 hr after receiving a subcutaneous injection of human interferon-α2b. Interferon produced a small decrease (median = 15%; range = 3% to 35%) in erythromycin metabolism (p < 0.05), as determined by 2-hr excretion of 14CO2 in the breath. Thus interferon-mediated suppression of cytochrome P-450 3A is less strong in human subjects than in male rats. Comparison of our data about the effect of interferon on cytochrome P-450 3A activity with earlier observations of a major impairment of theophylline clearance in human beings suggests that in human subjects interferon may have a more important effect on other drug-metabolizing enzymes, such as those of the cytochrome P-450 1A subfamily. However, interferon may produce clinically relevant impairment in the elimination of drugs that are substrates for cytochrome P-450 3A, should such agents have a narrow therapeutic index. (Hepatology 1993;17:230-235.)
Portal hypertension in lymphoproliferative and myeloproliferative disorders: Hemodynamic and histological correlations
Authors: Dubois Alain , Dauzat Michel , Pignodel Christine , Pomier-Layrargues Gilles , Marty-Double Christiane , Lopez François-Michel , Janbon Charles
Published: March 2007

The pathogenesis of portal hypertension in patients with lymphoproliferative and myeloproliferative disorders is not fully understood. We investigated 20 patients with myeloproliferative disease and 47 patients with lymphoproliferative disease. Transvenous liver biopsies and hepatic vein pressure gradient measurements were performed in all patients, and portal vein blood flow was measured by pulsed Doppler sonography in 31 of these patients and in 22 normal volunteers. The hepatic vein pressure gradient was significantly higher in patients with hepatic infiltrates, fibrosis or both than in patients without hepatic lesions (8.3 ± 5.0 mm Hg vs. 4.1 ± 2.3 mm Hg; p < 0.01). Portal vein blood flow was significantly higher in patients with hematological disease than in normal volunteers (31.2 ± 15.5 ml/min · kg vs. 14.2 ± 4.6 ml/min · kg; p < 0.01). In 81.8% of patients with hepatic infiltrates, fibrosis or both and increased portal vein blood flow, the hepatic vein pressure gradient was greater than 6 mm Hg. Although we saw a significant correlation between splenic vein blood flow and portal vein blood flow (n = 20; p < 0.01), we found no significant correlation between splenic vein blood flow and hepatic vein pressure gradient or spleen size. Hepatic infiltration and fibrosis appear to be major determinants of increased hepatic vein pressure gradient, probably because they increase intrahepatic vascular resistance. The role of increased splenic blood flow is probably not determinant. However, because portal pressure was not measured directly in this study, the incidence of portal hypertension may have been underestimated. (Hepatology 1993;17:246-250.)
Spontaneous bacterial peritonitis in cirrhosis: Predictive factors of infection resolution and survival in patients treated with cefotaxime
Authors: Toledo Claudio , Salmerón Joan-Manuel , Rimola Antoni , Navasa Miquel , Arroyo Vicente , Llach Josep , Ginés Angels , Ginès Pere , Rodés Joan
Published: March 2007

Cefotaxime is the most commonly used antibiotic for initial therapy of spontaneous bacterial peritonitis in cirrhosis. However, since the introduction of cefotaxime no study has been performed to investigate factors influencing prognosis in cirrhotic patients with this type of infection. In this study, predictive factors for infection resolution and patient survival were investigated in 213 consecutive episodes of spontaneous bacterial peritonitis in 185 cirrhotic patients. All patients were initially treated with cefotaxime. One hundred sixty-five episodes (77%) resolved with cefotaxime alone, and two more episodes (1%), initially unresponsive to cefotaxime, were cured after modification of antibiotic therapy. In a multivariate analysis (stepwise logistic regression), only 4 of 51 clinical and laboratory variables obtained at the time of diagnosis of infection were identified as independent predictors of infection resolution: band neutrophils in white blood cell count, community-acquired vs. hospitalacquired peritonitis, blood urea nitrogen level and serum aspartate aminotransferase level. No patient experienced serious adverse effects related to cefotaxime. Eighty-two patients died during hospitalization (38% mortality rate in relation to the 213 episodes of peritonitis). In the multivariate analysis, six variables were independently correlated with survival: blood urea nitrogen level, serum aspartate aminotransferase level, community-acquired vs. hospitalacquired peritonitis, age, Child-Pugh score and ileus. No microbiological data had predictive value for infection resolution or survival. These results indicate that in cirrhotic patients with spontaneous bacterial peritonitis treated with cefotaxime, infection resolution and patient survival may be predicted by several clinical and laboratory variables obtained at the time of infection diagnosis; the most important are blood urea nitrogen level, serum aspartate aminotransferase level and site (community or hospital) of peritonitis acquisition. (Hepatology 1993;17:251-257.)
Development of a bioartificial liver: Properties and function of a hollow-fiber module inoculated with liver cells
Authors: Rozga Jacek , Williams Frederick , Ro Man-Soo , Neuzil Daniel F. , Giorgio Todd D. , Backfisch Gisela , Moscioni Albert D. , Hakim Raymond , Demetriou Achilles A.
Published: March 2007

We have developed a bioartificial liver support system utilizing hollow-fiber bioreactor, plasmapheresis and microcarrier cell culture technologies. Liver cells were obtained through portal vein perfusion with ethylenediaminetetraacetate or ethylenediaminetetraacetate/collagenase. A mathematical model of mass transport in a hollow-fiber module, at various plasma flow velocities and system configurations, was developed. The bioartificial liver's ability to carry out specific differentiated metabolic liver functions was tested in vitro and in vivo. A reproducible large-animal model of acute ischemic liver failure was developed. Most major first-generation cyclosporine and 19-norterstosterone metabolites were isolated after substrate addition to the bioartificial liver in vitro. After bioartificial liver treatment for 6 hr (with dog or pig liver cells), dogs with acute liver failure had significantly lower serum ammonia and lactate levels and significantly higher serum glucose levels than did control animals treated with a bioartificial liver system inoculated with microcarriers alone. In addition, bioartificial liver-treated animals had significantly higher mean systolic blood pressures than did controls. Liver cell viability at the end of the 6-hr in vivo experiment was greater than 90%. (Hepatology 1993;17:258-265.)
Hyaluronic acid uptake by the isolated, perfused rat liver: An index of hepatic sinusoidal endothelial cell function
Authors: Deaciuc Ion V. , Bagby Gregory J. , Lang Charles H. , Spitzer John J.
Published: March 2007

Previous studies indicate that sinusoidal endothelial cells bind and internalize hyaluronic acid at much greater rates than do other liver cells. Thus hepatic hyaluronic acid removal rate may be indicative of sinusoidal endothelial cell function. In these studies the uptake of hyaluronic acid (molecular weight 1.3 × 106) was measured in isolated perfused rat liver under a variety of conditions. Uptake was dependent on hyaluronic acid concentration. At all concentrations tested, the rate of hyaluronic acid uptake stabilized at a steady-state level 2 to 3 min after development of a high rate of apparent uptake. At saturating hyaluronic acid concentration (150 ng · ml−1), the steady-state uptake rate was 10.4 ± 1.0 μg · gm−1 liver wet wt · hr−1 which is as high as or higher than the rates reported for isolated rat liver sinusoidal endothelial cells. The half-maximal rate of uptake was attained at a hyaluronic acid concentration of 80 ng · ml−1. Hyaluronic acid uptake was inhibited by heparin (80%), a competitive ligand for the hyaluronic acid receptor on sinusoidal endothelial cells; 4β-phorbol 12β-O-myristoyl 13α-acetate (25% to 50%), a tumor promoter and activator of protein kinase C; prostaglandin F2α (24% to 52%), an eicosanoid secreted in the liver by Kupffer cells; A23187 (33% to 66%), a Ca2+ ionophore; and Escherichia coli lipopolysaccharide (16% to 43%). Platelet activating factor did not affect hyaluronic acid uptake by the perfused liver. Hyaluronic acid uptake was increased by 50% after a 24-hr fast. Because previous studies indicate that the hepatic sinusoidal endothelial cells are almost exclusively responsible for the hepatic clearance of circulating hyaluronic acid, this study suggests that measurement of hyaluronic acid uptake by the perfused liver may allow assessment of sinusoidal endothelial cell function under the conditions in which the in vivo architecture of the liver remains intact. (Hepatology 1993;17:266-272.)
Liver regeneration after hepatic ischemia and reduced liver autotransplantation in the rat
Authors: Bolitho Glynn , Engelbrecht Gert , Lotz Zoe , Tyler Marilyn , McLeod Heather , Jaskiewicz Kaz , Hickman Rosemary
Published: March 2007

Current knowledge of liver regeneration after reduced liver transplantation is limited. Warm ischemia is one component of the reduced liver transplantation procedure that could have an impact on the regenerative response. To study this effect, we performed partial hepatectomy on male Long-Evans rats, with animals divided into four groups: group 1 underwent partial hepatectomy only; group 2 underwent partial hepatectomy and 40 min of ischemia; group 3 underwent partial hepatectomy, 40 min of ischemia and portocaval shunt surgery; and group 4 underwent partial hepatectomy and orthotopic autograft surgery. Group 5 consisted of sham-operated animals. Animals were killed 4, 24, 48, 72 and 96 hr after surgery. Thymidine kinase activity, mitotic index, a liver mass index and ornithine decarboxylase levels were used as parameters of liver regeneration. Aspartate transaminase was recorded. Maximal thymidine kinase and mitotic index were observed in group 1 animals at 24 hr. In groups 2, 3 and 4 maximal thymidine kinase activity and mitotic activity were observed 24 hr later at 48 hr. The magnitude of the peak response in these groups appeared to correlate with the duration of portal venous occlusion, with greatest increases occurring in those groups where portal stasis was most prolonged. The increase in liver mass for these groups was also delayed with respect to group 1 animals. The anticipated peak in ornithine decarboxylase levels was seen at 4 hr in group 1. The ornithine decarboxylase response in the other groups was disorganized, with delay of the recorded peaks. Therefore surgical procedures involving warm hepatic ischemia result in a delay in the first wave of DNA synthesis and mitosis in regenerating rat liver. This delayed response may reflect the effects of denervation, stimulation of cytokine release or diversion of hepatocyte synthetic function toward essential protein synthesis at a time critical to the survival of the animal. (Hepatology 1993;17:273-279.)
Zonation of cholesterol and glycerolipid synthesis in regenerating rat livers
Authors: Cheng Hui-Cheng , Yang Chuen-May , Shiao Ming-Shi
Published: March 2007

Hepatic zonation of cholesterol and glycerolipid synthesis was investigated in regenerating rat livers 24 hr after partial hepatectomy. Tritiated acetate and [U-14Clglycerol were injected into rats' peritoneal cavities for a short-term labeling study. Periportal and perivenous hepatocytes were isolated by digitonin collagenase perfusion. Cholesterol synthesis was significantly higher in periportal hepatocytes of the sham-operated livers (periportal/perivenous = 1.67; p < 0.05). Twenty-four hours after partial hepatectomy, cholesterol synthesis was selectively decreased by 40% (p < 0.01) in periportal hepatocytes. Consequently, hepatic zonation of cholesterol synthesis was abolished in regenerating livers. To study the cholesterol homeostasis on a long-term basis, we substituted deuterated water (25% enriched) for drinking water for 5 days to label newly synthesized cholesterol in a steady state. This procedure clearly demonstrated the net negative cholesterol balance 24 hr after partial hepatectomy. However, the newly synthesized cholesterol contributed equally to the cellular cholesterol pool in both zones. The synthesis of glycerolipids, whether measured from tritiated acetate or [U-14C]glycerol, was significantly increased without apparent zonation in the regenerating livers (twofold increase in phospholipid, and threefold to sevenfold increase in triacylglycerol). We concluded that hepatic zonations of cholesterol synthesis is caused by higher de novo synthesis in periportal hepatocytes, which is abolished in regenerating livers. No zonation of glycerolipid synthesis exists in normal and regenerating livers. (Hepatology 1993;17:280-286.)
Stimulation of the collagen α1(I) endogenous gene and transgene in carbon tetrachloride-induced hepatic fibrosis
Authors: Brenner David A. , Veloz Linda , Jaenisch Rudolf , Alcorn Joseph M.
Published: March 2007

Cirrhosis is characterized by a marked increase in the deposition of type I collagen and in the expression of the type I collagen genes α1(I) and α2(I). Although α1(I) gene regulation has been extensively studied in cultured cells, these results may not be applicable to hepatic fibrogenesis in vivo. Therefore the regulation of the α1(I) endogenous gene and an α1(I) transgene was studied in a transgenic mouse model that has a single copy of a human α1(I) gene segment containing the structural gene and 1.6 Kb of 5′ DNA and 20 Kb of 3′ DNA. To initiate hepatic fibrogenesis, we treated mice with the hepatotoxin carbon tetrachloride, either in a single dose or in biweekly doses for a period of 3 to 8 wk. Subsequently, hepatic α1(I) messenger RNA levels were determined by a species-specific RNase protection assay. Carbon tetrachloride injections co-ordinately increased the messenger RNA levels of the α1(I) endogenous gene and the transgene, both immediately and after 8 wk. These experiments demonstrate that this α1(I) transgene fragment contains information sufficient for appropriate basal and carbon tetrachloride-stimulated hepatic expression. They further demonstrate that sufficient homology exists between the human and mouse regulatory elements for the recognition of human cis-acting elements by mouse trans-acting factors. Thus transgenic mice provide a unique model in which to characterize the collagen α1(I) regulatory elements that are required in vivo for pathophysiological responses. (Hepatology 1993;17:287-292.)
Morphometry of the liver after liver transplantation in the rat: Significance of an intact arterial supply
Authors: Zhao Delai , Zimmermann Arthur , Wheatley Anthony M.
Published: March 2007

Two models of orthotopic liver transplantation in the rat currently used are with and without reconstruction of the hepatic artery. The aim of this study was to assess the importance of the arterial blood supply to liver structure after orthotopic liver transplantation with advanced morphometric methods. Orthotopic liver transplantation was performed in male Lewis rats, of which 11 underwent reconstruction of the hepatic artery and 11 did not. A group of untreated controls (n = 5) and a group of animals with hepatic artery ligation (n = 4) were included. Eight weeks after surgery liver tissue was harvested and subjected to systematic random sampling. A point-counting method was used, volume fractions of tissue components were determined. Liver samples from rats that underwent hepatic artery reconstruction had preserved lobular architecture, and estimated bile duct (0.71% ± 0.33% [S.D.]) and connective tissue (1.89% ± 0.52%) volumes were not significantly different from those of controls (bile duct, 0.34% ± 0.17%; connective tissue, 0.70% ± 0.07%). In contrast, liver samples from rats that did not undergo hepatic artery reconstruction showed bile duct proliferation (7.19% ± 4.83%; p < 0.05) and an increase in connective tissue volume (7.54% ± 3.68%; p <0.05) associated with a decrease in hepatocyte volume (controls, 87.3% ± 0.3%; rats that underwent arterialization, 85.5% ± 1.0%; rats that did not undergo arterialization, 73.2% ± 8.2% [p < 0.05]). Interestingly, hepatic artery ligation had no significant effect on any parameter. These findings show that in contrast to orthotopic liver transplantation with arterialization, orthotopic liver transplantation without arterialization may lead to derangement of liver structure, thus demonstrating the crucial role of an intact arterial supply for the biliary tree in orthotopic liver transplantation. The lack of change with hepatic artery ligation may indicate the presence of an additional arterial supply to the bile duct under normal conditions. (Hepatology 1993;17:310-317.)
Push me-pull you: The challenge of endocytic sorting
Authors: Crawford James J.
Published: March 2007

The vectorial nature of hepatocyte receptor-mediated endocytosis (RME) and its susceptibility to cytoskeletal disruptors has suggested that a polarized network of microtubules plays a vital role in directed movement during sorting. Using as markers a wellknown ligand, asialoorosomucoid, and its receptor, we have isolated endocytic vesicles that bind directly to and interact with stabilized endogenous hepatocyte microtubules at specific times during a synchronous, experimentally initiated, single wave of RME. Both ligand- and receptor-containing vesicles copelleted with microtubules in the absence of ATP but did not pellet under similar conditions when microtubules were not polymerized. When 5 mM ATP was added to preparations of microtubule-bound vesicles, ligand-containing vesicles were released into the supernatant, while receptor-containing vesicles remained immobilized on the microtubules. Release of ligand-containing vesicles from microtubules was prevented by monensin treatment during the endocytic wave. Several proteins, including the microtubule motor protein cytoplasmic dynein, were present in these preparations and were released from microtubule pellets by ATP addition concomitantly with ligand. These results suggest that receptor domains within the endosome can be immobilized by attachment to microtubules so that, following monensin-sensitive dissociation of ligand from receptor, ligand-containing vesicles can be pulled along microtubules away from the receptor domains by a motor molecule, such as cytoplasmic dynein, thereby delineating sorting.
Non-A, non-B posttransfusion hepatitis: Comparing C and non-C hepatitis
Authors: Koretz Ronald L. , Brezina Maria , Polito Alan J. , Quan Stella , Wilber Judith , Dinello Robert , Gitnick Gary
Published: March 2007

Using assays to detect antibodies against antigens (C-100, 5-1-1, C-22 and C-33) of the hepatitis C virus, we tested stored sera from 40 patients prospectively identified as having non-A, non-B posttransfusion hepatitis. The 28 patients who demonstrated seroconversion (“documented hepatitis C”) had more severe initial disease; all 20 cases of chronic hepatitis occurred in this subgroup. Only 2 of the 12 patients who did not demonstrate such seroconversion even had symptoms. In the group of patients with documented hepatitis C, chronic hepatitis was more commonly seen in men (89%) than in women (40%). The patients in whom antibody to the C-100 antigen developed were younger and had received more blood than had those patients who had hepatitis C diagnosed by demonstration of antibodies to the 5-1-1, C-22 or C-33 antigen (or all three). The proportion of cases of posttransfusion hepatitis that could be associated with antibody seroconversion decreased around the time that blood banks switched to an all-volunteer system. The hepatitis seen in patients who failed to demonstrate serological evidence of hepatitis C virus exposure was usually clinically unimportant; it may or may not have been due to viral infection. (Hepatology 1993;17:361-365.)
The intraportal lymphoid nodule and its environment in chronic active hepatitis C: An immunohistochemical study
Authors: Mosnier Jean-François , Degott Claude , Marcellin Patrick , Hénin Dominique , Erlincer Serge , Benhamou Jean-Pierre
Published: March 2007

Intraportal lymphoid nodules have been observed in liver biopsy specimens from patients with autoimmune liver disease and chronic active hepatitis C. They are characterized by a nodular lymphocyte aggregate with a germinal center. The purpose of this in situ immunophenotyping study was to determine immunohistochemically the phenotype of immunocompetent cells in and around intraportal lymphoid nodules in patients with chronic hepatitis C. For comparison, we also examined lymphoid nodules in patients with autoimmune liver disease. Liver biopsy specimens from 13 unselected patients with CAH and hepatitis C antibodies and from 7 unselected patients with autoimmune liver disease seen during the same period were studied. Sections of snap-frozen specimens were immunostained with monoclonal antibodies directed against different subsets of T cells, B cells, follicular dendritic cells and macrophages. Intraportal lymphoid nodules were observed in 11 of 13 patients with chronic hepatitis C. They appeared as lymphoid follicles with activated B cells in germinal centers surrounded by a follicular dendritic cell network. A mantle zone of B cells was present around the aggregate of activated B cells. A T-cell zone comprising CD4-positive helper T cells, CD8-positive suppressor/cytotoxic T cells and a few CD25-positive activated T cells expressing interleukin-2 receptor was seen at the periphery of the nodules. Human leukocyte antigen DR was expressed by B cells and by T cells, indicating that T cells were activated. The immunocompetent cells observed in piecemeal necrosis were predominantly CD4 helper T cells, whereas those seen in the lobule were predominantly CD8 suppressor/cytotoxic T cells. Some polytypic plasma cells were present in piecemeal necrosis. Intraportal lymphoid nodules were also observed in one patient with type 1 autoimmune chronic hepatitis and in one patient with primary sclerosing cholangitis. These nodules had a pattern indistinguishable from that observed in the patients with chronic hepatitis C. Similarly, immunocompetent cells of piecemeal necrosis and liver lobule shared a similar phenotype. We conclude that intraportal lymphoid nodules seen in chronic hepatitis C may be true functional lymphoid follicles, which induce stimulation of effector T cells and B cells. The characteristics of the nodules, their similarity with those observed in autoimmune liver disease and the presence of autoantibodies suggest an immune mechanism in the liver injury of chronic hepatitis C virus infection. (Hepatology 1993;17:366-371.)
Variability in the expression of a β2-microglobulin epitope on hepatocytes in chronic type C hepatitis on treatment with interferon
Authors: García-Buey Luisa , López-Botet Miguel , García-Sánchez Asunción , Balboa María A. , Aramburu José , García-Monzón Carmelo , Acevedo Agustín , Moreno-Otero Ricardo
Published: March 2007

Cytotoxic CD8+ T lymphocytes recognize viral antigens in the context of human leukocyte antigen class I molecule coexpression by target cells. Analysis of β2-microglobulin reactivity is useful in evaluating changes in human leukocyte antigen class I antigen distribution. In this study we analyzed liver biopsy specimens obtained from 15 patients with chronic active hepatitis type C who underwent a clinical trial with recombinant interferon-α2b. We comparatively studied by immunohistochemical analysis the expression of human leukocyte antigen class I antigens in frozen liver samples obtained before entry in the protocol and in specimens taken 8 mo after initiation of treatment. Six normal liver samples were used as controls. For immunohistochemical analysis, a panel of several human leukocyte antigen class I monoclonal antibodies, specific for β2-microglobulin or different heavy-chain determinants, was used. In addition, we included a novel monoclonal antibody (HP-1H8), characterized in this report, which is specific for a distinct β2-microglobulin epitope. On entry, mean serum ALT was 240 ± 89 IU/L and mean Knodell's index was 9.9 ± 2.4, whereas at the time of the second biopsy mean values had diminished to 45 ± 22 IU/L and 4.7 ± 3.0, respectively. Liver sections from controls and patients expressed human leukocyte antigen class I light- and heavy-chain determinants in hepatocytes, biliary duct epithelium, sinusoidal lining cells and lymphocytes. Remarkably, the β2-microglobulin epitope recognized by the HP-1H8 monoclonal antibody was undetectable on hepatocytes from normal livers but clearly evident on hepatocytes from patients with chronic active hepatitis C before interferon treatment. Positive staining was more intense in areas of piecemeal and lobular necrosis. Double immunostaining with a CD2 monoclonal antibody demonstrated that labeling with HP-1H8 was predominantly associated with T-cell infiltration. Interestingly, the reactivity of HP-1H8 with hepatocytes was diminished or disappeared in specimens obtained during interferon treatment; the pattern of reactivity then resembled that of samples from normal controls. Our data indirectly suggest that, in addition to the increased expression of human leukocyte antigen class I molecules on hepatocytes in viral infections, conformational changes may take place in these antigens. These changes can be revealed by immunostaining with the HP-1H8 monoclonal antibody. Interferon therapy could down-regulate this expression through its effect in reducing the histological activity resulting from the lysis of virus-infected hepatocytes by cytotoxic T cells. (Hepatology 1993;17:372-382.)
Interferon-α and zidovudine combination therapy for chronic hepatitis B: Results of a randomized, placebo-controlled trial
Authors: Janssen Harry L. A. , Berk Luuk , Heijtink Rudolf A. , Ten Kate Fiebo J. W. , Schalm Solko W.
Published: March 2007

Interferon-α therapy leads to HBeAg seroconversion in only one third of patients with chronic hepatitis B. In an attempt to increase the seroconversion rate, we investigated the combination of interferon-α and zidovudine in a subset of patients with presumably low response rates for interferon-α monotherapy. In a double-blind, controlled trial, 24 HBeAg-positive patients were randomized to receive lymphoblastoid interferon-α in subcutaneous doses increasing to 5 MU daily, combined with zidovudine given orally in doses increasing from 500 to 1,000 mg/day or with placebo for 16 wk. Treatment effects were monitored by quantitative assessment of HBV DNA, HBeAg and HBV DNA polymerase. Six months after termination of therapy, 1 of 12 (8%; 95% confidence interval = 2% to 39%) patients treated with interferon-α plus zidovudine and 2 of 12(17%; 95% confidence interval 2% to 48%) patients from the control group exhibited responses (HBeAg seroconversion). All patients remained HBsAg positive. The only responder of the interferon-α-zidovudine group relapsed after cessation of therapy, so none of the zidovudine-treated patients were HBeAg negative at the end of follow-up. No significant difference in AST level or in any of the virological markers was observed between the two groups during the course of the study. Adverse effects (anemia, leukopenia) necessitated reduction in the dose of zidovudine in 50% and of interferon-α in 42% of the patients treated with interferon-α plus zidovudine; in the control group these rates were 0% for placebo and 8% for interferon-α. In conclusion, the antiviral effect of interferon-α in chronic hepatitis B was not enhanced by additional zidovudine treatment. The combination therapy induced considerable side effects leading to dose reduction for both zidovudine and interferon-α. For combination therapy with interferon-α, oral nucleoside analogs with more potent antiviral effects and less toxicity than zidovudine should be developed. (Hepatology 1993;17:383-388.)
Recombinant interferon-α in inoperable hepatocellular carcinoma: A randomized controlled trial
Authors: Lai Ching-Lung , Lau Johnson Y. N. , Wu Pui-Chee , Ngan Henry , Chung Hau-Tim , Mitchell Stuart J. , Corbett Timothy J. , Chow Anthony W. C. , Lin Hsiang-Ju
Published: March 2007

To evaluate the clinical efficacy of interferon-α in hepatocellular carcinoma, 71 adult Chinese patients with histologically proven inoperable hepatocellular carcinoma were randomized to receive recombinant interferon-α2a (50 × 106 IU/m2) intramuscularly three times a week (n = 35) or no antitumor therapy (n = 36). The survival of interferon-α-treated patients was significantly better than that of patients who received no antitumor therapy (p = 0.0471); median lengths of survival were 14.5 and 7.5 wk, respectively. Objective tumor regression greater than 50% was observed in 31.4% (11 of 35) of patients receiving interferon-α. Interferon-α induced tumor regression greater than 50% in 11(31.4%) patients. Compared with the group receiving no antitumor therapy, the interferon-α therapy group had more tumor regression (p < 0.0001) and less tumor progression (p = 0.001). This high-dose interferon-α therapy was relatively well tolerated; only 34.3% of patients required reduction of dosage by one third or one half because of persistent fatigue. Two patients with diabetes mellitus (one also had tabes dorsalis) exhibited mental deterioration that might have been partially attributable to interferon-α therapy. We conclude that interferon-α is useful in a proportion of Chinese patients with inoperable hepatocellular carcinoma, both in prolonging survival and in inducing tumor regression. (Hepatology 1993;17:389-394.)
Formation of 7α- and 7β-hydroxylated bile acid precursors from 27-hydroxycholesterol in human liver microsomes and mitochondria
Authors: Shoda Junichi , Toll Anders , Axelson Magnus , Pieper Fritz , Wikvall Kjell , Sjövall Jan
Published: March 2007

In a search for enzymes involved in the formation of bile acids from 27-hydroxycholesterol in humans, the metabolism of this and other side-chain oxygenated steroids was studied in human liver microsomes and mitochondria. The microsomal fraction contained enzyme(s) catalyzing 7α-hydroxylation of 27-hydroxycholesterol and 3β-hydroxy-5-cholestenoic acid, whereas the 7α-hydroxylation of cholesterol and 3β-hydroxy-5-cholenoic acid was low. Only small amounts of 7β-hydroxylated products were formed. Purification and subfractionation of microsomal protein yielded a fraction of cytochrome P-450, which required NADPH and NADPH-cytochrome P-450 reductase and catalyzed 7α-hydroxylation of the side-chain oxygenated 3β-hydroxy-δ5-C27-steroids but was inactive toward cholesterol. Added cholesterol did not inhibit the observed enzymatic activity. The results provide evidence that this enzyme is different from cholesterol 7α-hydroxylase. The mitochondrial fraction contained enzyme(s) that catalyzed an isocitrate-dependent 7α-hydroxylation of 3β-hydroxy-5-cholestenoic acid. The activity was much lower with 27-hydroxycholesterol. The mitochondrial fraction also catalyzed the oxidation of the 27-hydroxy group and contained a 3β-hydroxy-δ5-steroid dehydrogenase active on 7α-hydroxylated C27-steroids. The metabolic end product of the reactions catalyzed by these enzymes was 7α-hydroxy-3-oxo-4-cholestenoic acid. A considerable fraction of the 7α-hydroxy-δ5 intermediates was also converted to the corresponding 7β-hydroxysteroids, probably by way of the 7-oxosteroids, suggesting the presence of an epimerizing enzyme in the mitochondrial fraction. This study shows that 7α-hydroxy-3-oxo-4-cholestenoic acid, which is believed to be an important precursor of chenodeoxycholic acid in human beings, can be formed from 27-hydroxycholesterol or 3β-hydroxy-5-cholestenoic acid by the action of 7α-hydroxylases present in the microsomal and mitochondrial fractions. These enzymes, found to be more active in humans and pigs than in rats and rabbits, can catalyze the formation of bile acids by way of pathways that bypass the microsomal cholesterol 7α-hydroxylase as the rate-limiting enzyme. (Hepatology 1993;17:395-403.)
Peroxisomes in cirrhosis of the human liver: A cytochemical, ultrastructural and quantitative study
Authors: De Craemer Dirk , Pauwels Marina , Roels Frank
Published: March 2007

Hepatocellular peroxisomes in 32 patients with cirrhosis were studied by means of catalase cytochemical and morphometric analysis. Seven normal human livers were used as controls. The severity of the cirrhosis was determined with the Child-Turcotte criteria. Under the light microscope, a decrease in catalase staining was observed in 12 livers. Staining showed a weak inverse correlation with severity of the cirrhotic process. Peroxisomes revealed a perinuclear configuration in 24 patients. Morphometric analysis of peroxisomes was performed on 14 cirrhotic livers and revealed a near doubling of the number of organelles, with a compensatory decrease in mean peroxisomal diameter: no appreciable change in total volume of the peroxisome compartment was found. Cytoplasmic invaginations, protrusions and gastruloid cisternae were sparse. Apparently, peroxisomal proliferation in liver cells appeared early in the cirrhotic process. In all 10 livers with a perinuclear configuration of the peroxisomes that were processed for electron microscopy, a morphometrically confirmed increase in the number of peroxisomes was observed. Peroxisomes frequently showed transparent matrical spots and angular profiles. In two patients nucleoid-containing peroxisomes were observed. Although variation between individual patients was high, peroxisomal changes were observed in each cirrhotic liver. No relationship between morphological or morphometric alterations in peroxisomal compartment on one side and the severity of the disease or the type of cirrhotic nodules on the other side was observed. (Hepatology 1993;17:404-410.)
Creatine kinase-BB: A marker of liver sinusoidal damage in ischemia-reperfusion
Authors: Vaubourdolle Michel , Chazouilleres Olivier , Poupon Raoul , Ballet François , Braundwald Jacqueline , Legendre Claire , Baudin Bruno , Kirn André , Giboudeau Jacqueline
Published: March 2007

Cell damage within the sinusoidal lining of human liver grafts during transplantation is an early event that is critical in ischemia-reperfusion injury and probably plays a key role in primary liver dysfunction after transplantation. No simple biochemical marker for sinusoidal injury is currently available. Because creatine kinase activity has been described in heart endothelial cells, we hypothesized that release of this enzyme might serve as an index of sinusoidal injury. To test this hypothesis, we used several in vivo and in vitro experimental models. Occlusion of the rat hepatic pedicle in situ for 60 min (normothermic ischemia) induced a significant increase in serum creatine kinase levels relative to those in laparotomized controls (2,530 ± 530 vs. 389 ± 64 IU/L, mean ± SEM; p < 0.005). In the isolated perfused rat liver, 60-min ischemia induced early (≤ 3 min) creatine kinase and AST release (0.87 ± 0.14 vs. 0.08 ± 0.01 IU/min/gm liver, respectively). A similar phenomenon was observed after 24-hr or 48-hr hypothermic conservation in University of Wisconsin solution. Electrophoretic analysis and immunoinhibition studies showed that creatine kinase activity comprised creatine kinase-BB (≈ 50%) and mitochondrial creatine kinase. Trypan blue infusion showed a loss of viability in sinusoidal cells, whereas hepatocytes were relatively spared. Finally, murine sinusoidal cells were isolated, cultured and then lysed by a freeze-thaw cycle and sonication. Creatine kinase activity was found in endothelial cells (creatine kinase-BB), Kupffer cells (creatine kinase-BB) and Ito cells (creatine kinase-MM). Creatine kinase-BB was not found in hepatocytes, but mitochondrial creatine kinase was detected. These results indicate that liver ischemia-reperfusion injury induces a release of creatine kinase-BB from sinusoidal cells and of mitochondrial creatine kinase from hepatocytes, suggesting that creatine kinase-BB activity could provide a simple index of cell damage within the sinusoidal lining. (Hepatology 1993;17:423-428.)
Administration of hepatic stimulatory substance alone or with other liver growth factors does not ameliorate acetaminophen-induced liver failure
Authors: Francavilla Antonio , Azzarone Alessandro , Carrieri Guiseppe , Cillo Umberto , Van Thiel David , Subbottin Vladimir , Starzl Thomas E.
Published: March 2007

Sixty-two beagle dogs were given three doses of acetaminophen over a period of 24 hr in a fulminant liver failure model that is 70% lethal in 72 hr. Treatment of the animals with hepatic stimulatory substance alone or in a mixture with insulin, transforming growth factor-α and insulin-like growth factor II had no effect on mortality. Evidence of maximum regeneration with a mitotic index 20 to 25 times resting was the same in treated and untreated animals. Similarly, the biochemical and hematological indexes of liver injury were unaffected by therapy. These studies illustrate the futility of treating fulminant liver failure with exogenous growth factors that apparently are already present in large amounts in the natural response to liver injury. The results suggest that on-going liver injury by mechanisms other than lack of growth factors is the central problem of fulminant liver failure. If so, provision of regeneration-stimulating substance is an inappropriate therapeutic strategy. (Hepatology 1993;17:429-433.)
Effects of dietary cholesterol on bile formation and hepatic processing of chylomicron remnant cholesterol in the rat
Authors: Smit Martin J. , Kuipers Folkert , Vonk Roel J. , Temmerman Arno M. , Jäckle Stefan , Windler Eberhard E. T.
Published: March 2007

We have studied the coupling between hepatic uptake of chylomicron remnant cholesteryl ester and biliary excretion of cholesterol and bile acids in rats, after feeding them a cholesterol-free (control) or a high-cholesterol diet (1% wt/wt) for 2 wk. We equipped rats with permanent catheters in the bile duct, duodenum and heart to allow experiments in unanesthetized, unrestrained animals. Cholesterol feeding induced a 20% increase in plasma cholesterol concentration, a threefold increase in hepatic bile acid synthesis and a 27% increase in bile acid pool size, whereas biliary excretion of cholesterol was decreased by 50%. The enlarged bile acid pool contained relatively less cholic acid and more chenodeoxycholic acid and muricholic acids. [3H]cholesteryl ester-labeled chylomicron remnants (150 μg protein per rat) were injected intracardially, and blood and bile were collected for a period of 22 hr. Plasma disappearance of remnants was significantly delayed by cholesterol feeding, probably caused by competition with dietinduced β-very low density lipoproteins for hepatic uptake. In control rats biliary excretion of chylomicron remnant-derived radioactivity (50% in free cholesterol and 50% in bile acids) showed an initial peak 1 hr after injection (2.4% dose per hour). A second peak (90% in bile acids), amounting to 1.5% of the dose per hour, appeared 11 hr after injection. Total 22-hr excretion of 3H was 22% of the dose. In cholesterol-fed rats chylomicron remnant-derived radioactivity appeared more rapidly in bile, with a peak 1 hr after injection, amounting to 3.5% of the dose per hour. In this case radioactivity was mainly present as bile acid. Total excretion in 22 hr was 27% of the dose. We conclude that chylomicron remnant uptake by the liver is efficiently coupled to bile acid synthesis and biliary excretion, thus providing an efficient pathway for removal of intestine-derived cholesterol. After cholesterol feeding, chylomicron remnant cholesteryl ester is more efficiently converted to bile acids, a mechanism which may contribute to the resistance of rats to diet-induced elevation of plasma cholesterol. In contrast, biliary excretion in the form of free cholesterol, the second main excretory pathway, is significantly decreased by a high-cholesterol diet. (Hepatology 1993;17:445-454.)
Dissection of compartments in rat hepatocytes involved in the intracellular trafficking of high-density lipoprotein particles or their selectively internalized cholesteryl esters
Authors: Jäckle Stefan , Rinninger Franz , Lorenzen Thomas , Greten Heiner , Windler Eberhard
Published: March 2007

The trafficking of apolipoprotein E-deficient highdensity lipoprotein particles and of their component cholesteryl esters in rat hepatocytes was studied. Human high-density lipoprotein 3, labeled with two nondegradable, intracellularly trapped tracers in their apolipoprotein A-I and their cholesteryl esters, were injected into rats, and five subcellular hepatocytic fractions were isolated at various time intervals. In control experiments with homologous lipoproteins, doubly labeled rat high-density lipoproteins depleted of apolipoprotein E were used. In endosomes and lysosomes the two labels were recovered at near unity, indicating that high-density lipoproteins are endocytosed as particles, transported to early and late endosomes and finally subjected to lysosomal degradation. No significant amounts of label were found in receptorrecycling endosomes. In contrast to label of those of low-density lipoproteins, label of component protein and cholesteryl esters of high-density lipoproteins from isolated endosomes floated at different densities in gradient ultracentrifugation, indicating early disintegration of high-density lipoprotein particles. In contrast to the endocytic organelles, in the whole liver, label of high-density lipoprotein-associated cholesteryl esters exceeded the label of high-density lipoprotein-associated apolipoprotein A-I twofold to threefold. This finding is compatible with selective uptake of high-density lipoprotein cholesteryl esters in addition to uptake of high-density lipoprotein particles. The excess cholesteryl esters accumulated in a nonendosomal fraction, whose major proteins differed from the integral proteins of endosomes. These data suggest two distinct intracellular routes of hepatocytic high-density lipoprotein trafficking in vivo. Highdensity lipoproteins free of apolipoprotein E are internalized intact by hepatocytes, are predominantly transported to early and late endosomes and are finally subjected to lysosomal degradation. High-density lipo-protein particles do not undergo retroendocytosis in hepatocytes. In addition, high-density lipoprotein-associated cholesteryl esters can be taken up by hepatocytes selectively. They, however, accumulate in a nonendosomal, nonlysosomal compartment. (Hepatology 1993;17:455-465.)