bluuebunny/crossref_metadata_2025 huggingface dataset:
Extracellular Matrix Regulation of Hepatic Transcription Factors Is Dependent on Cell Structure
Authors: Schuetz Erin G.
Published: March 2007

The extracellular matrix (ECM) promotes tissue morphogenesis, cell migration, and the differentiation of a variety of cell types. However, the mechanisms by which ECM causes differentiated gene expression have been unknown. In this report, we show that culturing the hepatocyte–derived cell line H2.35 on an ECM gel changes cell morphology and selectively stimulates the transcription of a subset of liver–specific genes, including serum albumin. Transcriptional activation by ECM also occurs with transfected plasmids bearing the transcriptional enhancer of the albumin gene. ECM substrates of different composition activated the albumin enhancer only when the ECM promoted a cuboidal, differentiated cell morphology. Enhancer activation by the ECM was mediated by two liver transcription factors, HNF3α and eH–TF, which appear to be regulated differently by matrix. Specifically, we found that a collagen gel substratum caused a selective increase in the factor HNF3α at the levels of mRNA accumulation and DNA–binding activity in nuclear extracts, both in H2.35 cells and in the hepatoma cell line HepG2. We conclude that the ECM can stimulate cell differentiation by selectively activating transcriptional regulatory factors and that such regulation occurs coordinately with ECM–promoted changes in cell shape.
Intracranial Pressure Monitoring and Liver Transplantation for Fulminant Hepatic Failure
Authors: Lidofsky Steven D. , Bass Nathan M. , Prager Marie C. , Washington Denna E. , Read Alexandra E. , Wright Teresa L. , Ascher Nancy L. , Roberts John P. , Scharschmidt Bruce F. , Lake John R.
Published: March 2007

Cerebral edema and intracranial hypertension, commonly present in fulminant hepatic failure, may lead to brainstem herniation and limit the survival of comatose patients awaiting liver transplantation before a donor organ becomes available. Also, they are likely responsible for postoperative neurological morbidity and mortality. Although intracranial pressure monitoring has been proposed to aid clinical decision making in this setting, its use in the prevention of brainstem herniation preoperatively, in the selection of patients for liver transplantation who have the potential for neurological recovery and in the maintenance of cerebral perfusion during liver transplantation has not been examined in detail. To address these issues, we established a protocol for intracranial pressure monitoring in comatose patients with fulminant hepatic failure as part of their preoperative and intraoperative management. Twenty adults and three children underwent intracranial pressure monitoring. Ten patients required preoperative medical therapy with mannitol, barbiturates or both for a rise in intracranial pressure above 25 mm Hg. Four patients had a sustained lowering of intracranial pressure, three of whom survived hospitalization. Six patients had intracranial hypertension refractory to medical management, were removed from a waiting list for a donor organ and died with brainstem herniation. Of the remaining 17 patients, 3 died of other causes while awaiting a donor organ, 2 recovered spontaneously without neurological sequelae and 12 underwent liver transplantation. All but one patient undergoing liver transplantation had transient intraoperative intracranial hypertension develop, requiring medical treatment. The 12 patients who had transplants recovered neurologically and were discharged from the hospital. Survival after liver transplantation was 92% (range of follow–up = 3 to 37 mo), and the overall survival of the 23 monitored patients was 56.5%. The major complication of intracranial pressure monitoring was intracranial hemorrhage, which occurred in five patients and contributed to two patient deaths. Intracranial pressure monitoring represents a potentially important tool in the preoperative and intraoperative management of comatose patients with fulminant hepatic failure and warrants further study. (Hepatology 1992;16:1-7.)
The Mechanism of Inhibition of Hepatitis B Virus Replication by the Carbocyclic Analog of 2′–Deoxyguanosine
Authors: Price Peter M. , Banerjee Ranjit , Jeffrey Alan M. , Acs George
Published: March 2007

The carbocyclic analog of deoxyguanosine inhibits hepatitis B virus replication by greater than 95% in the hepatitis B virus–producing cell line (2.2.15) as monitored by decreases of secreted hepatitis B virus DNA, hepatitis B virus polymerase activity and intracellular episomal hepatitis B virus DNA. Transcription of hepatitis B virus RNA from chromosomally integrated hepatitis B virus DNA was unaffected. Radioactive carbocyclic 2′–deoxyguanosine was directly phosphorylated within the 2.2.15 cells and was incorporated exclusively into DNA. In contrast, radioactive deoxyguanosine was presumably metabolized through the “salvage” pathway in which the guanine was primarily incorporated into cellular RNAs. The rate of incorporation of carbocyclic 2′–deoxyguanosine in 2.2.15 cells was similar to that in the parental cell line (Hep G2), which does not contain hepatitis B virus sequences. Greater than 90% of the analog was present at internal sites within the DNA, indicating that the analog did not function as a DNA chain terminator. Kinetic analysis of the K
m and K
i of dGTP and carbocyclic 2′–deoxyguanosine 5′–triphosphate, respectively, using both hepatitis B virus polymerase and DNA polymerase δ indicated that the analog is a competitive inhibitor for dGTP. Although both polymerases had similar K
m's for dGTP, the K
i for carbocyclic 2′–deoxyguanosine 5′–triphosphate was about 6 times lower using the hepatitis B virus polymerase. This would indicate that, at low concentrations of intracellular carbocyclic 2′–deoxyguanosine 5′–triphosphate, the hepatitis B virus polymerase would be preferentially inhibited. We propose this to be the mechanism acting to inhibit preferentially hepatitis B virus replication in the tissue culture cells. (Hepatology 1992;16:8-12.)
Chronic Hepatitis B Virus Infection in An Anti–Hbc-Nonreactive Blood Donor: Variant Virus or Defective Immune Response?
Authors: Lee Jae-Hag , Paglieroni Teresa G. , Holland Paul V. , Zeldis Jerome B.
Published: March 2007

Viral sequence and host immune response were investigated in an unusual, asymptomatic chronic hepatitis B virus carrier (human leukocyte antigen type A24, Bw61, Bw62, Bw6, DRw11, DRw52, DQw7) who was consistently nonreactive for antibody to HBc and had a normal ALT level over a 5–yr study period. The precore and core region DNA sequences of virus isolated from his serum had seven silent mutations that resulted in no changes in the amino acid sequence of the adr HBsAg subtype. He had no abnormalities in the number of peripheral blood T or B cells and no HBcAg–specific suppressor T cells. His lymphocytes proliferated in vitro in response to phytohemagglutinin, pokeweed mitogen, Staphylococcus aureus and tetanus toxoid but not to recombinant HBcAg. Unlike other HBsAg carriers and hepatitis B virus-immune individuals, his monocytes did not ingest beads coated with HBcAg. Failure to produce antibody to HBc was not due to an hepatitis B virus variant but to a selective immune system defect in this asymptomatic HBsAg carrier. (Hepatology 1992;16:24-30.)
Hepatitis B Virus Dna in Peripheral–Blood Mononuclear Cells in Chronic Hepatitis B After Hbsag Clearance
Authors: Mason Andrew , Yoffe Boris , Noonan Christine , Mearns Mary , Campbell Carolyn , Kelley Amanda , Perrillo Robert P.
Published: March 2007

In this study, peripheral–blood mononuclear cells from patients with chronic hepatitis B and spontaneous or therapy–induced disappearance of HBsAg were examined for HBV DNA. Samples were evaluated by in situ hybridization and polymerase chain reaction both before and after clearance of HBsAg. By in situ hybridization, positive signals were observed in 2 of 13 samples collected after HBsAg loss, in 8 of 15 samples before HBsAg loss and in 0 of 4 control patients without serological markers of active or prior HBV infection. When polymerase chain reaction analyses were performed, HBV DNA was detected in 5 of 12 HBsAg–negative samples and 10 of 15 HBsAg–positive samples from the study group. Testing of mononuclear cells after disappearance of HBsAg revealed that two of eight patients were HBV DNA positive by in situ hybridization and by polymerase chain reaction, whereas two additional patients were positive by polymerase chain reaction alone. Mononuclear cell-associated HBV DNA was detected between 2 and 9 mo after the disappearance of circulating HBsAg by in situ hybridization and as long as 4 yr later by polymerase chain reaction. These data indicate that patients who have undergone HBsAg seroconversion may nonetheless harbor HBV DNA in their peripheral–blood mononuclear cells for prolonged periods. (Hepatology 1992;16:36-41.)
Refractory Ascites: Modulation of Atrial Natriuretic Factor Unresponsiveness by Mannitol
Authors: Morali Gilles A. , Tobe Sheldon W. , Skorecki Karl L. , Blendis Laurence M.
Published: March 2007

We have previously shown that unresponsiveness to atrial natriuretic factor is a marker of the severity of ascites. The tubular mechanisms are unknown, but it seems that increased reabsorption of sodium proximal to the main site of action of atrial natriuretic factor (i.e., the inner medullary collecting duct) plays an important role. We attempted to decrease the proximal reabsorption of sodium with mannitol in patients unresponsive to atrial natriuretic factor. The results of mannitol in such a group of patients has previously been conflicting. We studied 10 patients with massive, resistant ascites who were off diuretics and on a 20–mmol/day sodium diet for 7 days. Atrial natriuretic factor unresponsiveness was confirmed by failure of a 2–hr atrial natriuretic factor infusion to induce a natriuresis. The next day all patients received an infusion of 40 gm of mannitol and subsequently a combined infusion of mannitol and atrial natriuretic factor. Proximal reabsorption of sodium and water were evaluated by lithium clearance, and glomerular filtration rate and renal blood flow were evaluated by inulin clearance and p–aminohippurate clearances, respectively. Six patients responded to mannitol alone with an increased diuresis (from 39 ± 7 to 148 ± 35 ml/hr) and natriuresis (from 0.27 ± 0.05 mmol/hr to 1.65 ± 0.53 mmol/hr; p < 0.05) (responders), whereas four did not (nonresponders). The combination of atrial natriuretic factor and mannitol induced a further significant increase in sodium excretion (3.28 ± 0.68 mmol/hr) but not in urine excretion, compared with mannitol alone. Lithium clearance increased in the responders after mannitol infusion, but it did not increase further with ANF plus mannitol. Inulin and p–aminohippurate clearances were equally low in the two groups and did not change during the infusions. The responders had significantly lower plasma renin activity, aldosterone and norepinephrine levels than the nonresponders (plasma renin activity = 1.9 ± 0.7 vs. 7.3 ± 1.5 ng/L/sec; aldosterone = 2,830 ± 1,273 vs. 9,457 ± 3,873 pmol/L; norepinephrine = 2.6 ± 1.6 vs. 8.4 ± 1.6 nmol/L; p < 0.05).

We conclude the following: (a) atrial natriuretic factor unresponsiveness in cirrhotic patients is due, in part, to increased reabsorption of sodium proximal to the distal site of atrial natriuretic factor action; (b) increased proximal reabsorption of sodium might be mediated in part by increased renin aldosterone and sympathetic nervous system activity; with moderate as opposed to marked elevation, this effect can be overcome by mannitol; and (c) with increased mannitol–induced distal delivery of sodium, atrial natriuretic factor further increases sodium excretion, indicating that receptor or intracellular signaling of atrial natriuretic factor response remains intact. (Hepatology 1992;16:42-48.)
Reversal of Fulminant Hepatic Failure Using An Extracorporeal Liver Assist Device
Authors: Sussman Norman L. , Chong Maria G. , Koussayer Tarek , He Da-Er , Shang Thomas A. , Whisennand Hartwell H. , Kelly James H.
Published: March 2007

Liver transplantation is currently the only effective therapy for patients with fulminant hepatic failure. The availability of an artificial liver could bridge these patients through the relatively brief crisis period and allow their own livers to regenerate, providing a more favorable outcome and sparing the trauma and expense of transplant. We have developed a device consisting of a highly differentiated human liver cell line cultured in a hollow fiber cartridge. This device is capable of supporting dogs with acetaminopheninduced fulminant hepatic failure for a period long enough for their own livers to resume function. Even though liver function tests such as albumin and prothrombin time became extremely abnormal during the course of the experiment, the dogs did not become encephalopathic. Two of the three treated animals recovered sufficient liver function after 42 to 48 hr of treatment that they could be disconnected from the device, and they survived the experiment. Histological results and serum ALT levels suggest that the device affected the course of the disease in two animals, allowing recovery of hepatocytes that would otherwise have lysed. In the third animal, regenerative nodules demonstrated that, even in the presence of severe liver injury, the device was capable of supporting total liver function. (Hepatology 1992;16:60-65.)
Lack of Association Between Cytomegalovirus Infection, Hla Matching and the Vanishing Bile Duct Syndrome After Liver Transplantation
Authors: Paya Carlos V. , Wiesner Russell H. , Hermans Paul E. , Larson-Keller Jeffrey J. , Ilstrup Duane M. , Krom Ruud A.F. , Moore Breanndon S. , Ludwig Jurgen , Smith Thomas F.
Published: March 2007

In this study we evaluated the association between cytomegalovirus infection alone or in relation to human leukocyte antigen matching and the development of vanishing bile duct syndrome, a form of chronic hepatic allograft rejection.

A total of 81 consecutive liver transplant recipients were studied. Cytomegalovirus infection developed in 46 recipients (57%), and vanishing bile duct syndrome occurred in 9 recipients (11%). Cytomegalovirus infection developed in only five of the nine patients with vanishing bile duct syndrome. Univariate analysis of pretransplant recipient/donor cytomegalovirus serological tests and human leukocyte antigen typing showed they were not significant risk factors for the development of vanishing bile duct syndrome. Timedependent analysis of cytomegalovirus infection after transplantation as a risk factor for vanishing bile duct syndrome, in a multivariate analysis with human leukocyte antigen match, showed no statistical significance.

In our study, no association was found between cytomegalovirus infection alone or in relation to class I or II human leukocyte antigen match and the subsequent development of vanishing bile duct syndrome. (Hepatology 1992;16:66-70.)
Interrelationships of Bile Acid and Phospholipid Fatty Acid Species With Cholesterol Saturation of Duodenal Bile in Health and Gallstone Disease
Authors: Berr Frieder , Schreiber Edgar , Frick Ulrich
Published: March 2007

The relative amount of cholesterol and the fatty acid composition of phosphatidylcholines in bile can be influenced by the bile acid species secreted. To search for a contribution of secondary bile acids and of phosphatidylcholines to supersaturation of bile in gallstone disease, we compared the relative amount of cholesterol and the biliary composition of bile acids and of phospholipid fatty acids in cholecystokininstimulated duodenal bile of 22 female gallstone patients and 16 healthy controls and analyzed the interrelationships of these bile constituents. Gallstone patients had higher molar percentages of cholesterol than did controls (10.2 ± 3.2 vs. 6 ± 1.5 mol%; p < 0.001) and demonstrated a trend toward larger fractions of deoxycholic and lithocholic acids. By linear models, variation of cholesterol saturation could be predicted (p < 0.001) up to 53% by the bile acid pattern and up to 81% by the fatty acid pattern of phospholipids. Linear path analysis (goodness–of–fit index = 0.973) confirmed the tight relationship between phospholipid fatty acids (positive: oleic, arachidonic; negative: Iinoleic, palmitoleic) and the relative amount of cholesterol; more than half the influence of cholic, deoxycholic and lithocholic acids on the relative amount of cholesterol could be explained indirectly by their influence on the phospholipid fatty acid pattern. We conclude that the relationships examined by path analysis support the working hypothesis that secondary bile acids contribute to supersaturation of bile mainly by changing the fatty acid pattern of the secreted phospholipids (presumably the pattern of phosphatidylcholines), which increases the molar ratio of cholesterol/phospholipids in bile. (Hepatology 1992;16:71-81.)
Direct Measurement of Hepatic Blood Flow in Native and Transplanted Organs, With Accompanying Systemic Hemodynamics
Authors: Paulsen William A. , Klintmalm Goran B.G.
Published: March 2007

The purpose of this study was to investigate intraoperatively a population of patients with end–stage liver disease before and after liver transplantation with respect to (a) the range of hepatic and systemic hemodynamics and their changes associated with transplantation and (b) the ability to identify native hemodynamic correlates with specific diagnostic groups. Hepatic artery and portal vein blood flows were determined with square–wave electromagnetic flowmetry. Significant differences related to the type of preservation solution used-Euro–Collins or University of Wisconsin-were identified in some hepatic and systemic hemodynamic measurements from the graft livers. Specifically, cardiac output, total liver blood flow and liver weight were significantly increased in the Euro–Collins group compared with the native and University of Wisconsin groups. Hepatic artery flow was significantly greater and portal vein pressure was significantly lower in the University of Wisconsin group than in the native or Euro–Collins group. In general, comparing the graft and native livers, hepatic artery and portal vein blood flow increased significantly after transplantation, as did hepatic oxygen consumption. Portal vein pressures were dramatically reduced, but systemic arterial pressure remained remarkably constant. The percentage of cardiac output going to the liver increased, as did the portal vein percentage of the total liver blood flow.

Diagnostic groups could not clearly be associated with characteristic native liver or systemic hemodynamics. Hemodynamics may be associated more with the stage of the disease process than the disease itself. (Hepatology 1992;16:100-111.)
Morphological Differences Between Hepatocellular Carcinoma and Hepatocellular Carcinomalike Lesions
Authors: Motohashi Ikuko , Okudaira Masahiko , Takai Tomoko , Kaneko Satoshi , Ikeda Noriaki
Published: March 2007

In an attempt to provide a quantitative basis for differentiation between well–differentiated hepatocellular carcinoma and hepatocellular carcinomalike lesions (focal nodular hyperplasia, regenerative nodular hyperplasia and hepatocellular adenoma), histopathological and morphometrical analyses were performed on 208 cases of various liver diseases with the aid of an image analyzer. As practical indicators for hepatocellular carcinoma, the following six morphometrical features were established: (a) nuclear shape factor of less than 0.93, (b) coefficient of variance of nuclei of more than 5%, (c) average width of trabecular cords greater than three cells, (d) nucleocytoplasmic ratio increased to more than 0.3, (e) cellular density of more than 40 liver cells and (f) individual nuclear dimension larger than 50 μm2. The manifest categories increased with dedifferentiation of cells in hepatocellular carcinoma; the number and degree of cellular and structural atypia became more prominent. Data were analyzed statistically by two multivariate analyses. Logistic analysis was able to correctly separate hepatocellular carcinoma from conditions that were not hepatocellular carcinoma, including hepatocellular carcinomalike lesions. The incidence of 13 descriptive histopathological findings such as fibrous capsule, portal triads and clear–cell clusters were also compared in hepatocellular carcinomalike lesions and hepatocellular carcinomas graded according to Edmondson's classification. Presence of a fibrous capsule, portal triads, mosaiclike patterns and tumor vessels showed statistical differences between hepatocellular carcinomalike lesions and well–differentiated hepatocellular carcinoma by the χ2 test (p < 0.005). (Hepatology 1992;16:118-126.)
Multiple Nuclear Dots Antinuclear Antibodies Are Not Specific for Primary Biliary Cirrhosis
Authors: Pawlotsky Jean-Michel , Andre Chantal , Metreau Jean-Michel , Beaugrand Michel , Zafrani Elie-Serge , Dhumeaux Daniel
Published: March 2007

Multiple nuclear dots antinuclear antibodies display a specific immunofluorescence pattern on HEp–2 cells. They have been reported to be strongly associated with primary biliary cirrhosis, especially when sicca syndrome was present. To determine whether multiple nuclear dots antinuclear antibodies are specific for primary biliary cirrhosis, we studied the clinical, biochemical, immunological and morphological features of 38 patients between December 1983 and September 1990 who had serum multiple nuclear dots antinuclear antibodies detected in an immunology laboratory of a large medical center. Sufficient information was reliable in 36 patients; the group included 31 women and 5 men (mean age = 57.6 ± 14.5, range = 30 to 87). Fifteen patients (42%) had primary biliary cirrhosis, 5 patients (14%) had type 1 autoimmune chronic active hepatitis, 4 patients (11%) had liver disease of unknown cause and 12 patients (33%) had various immunological disorders but no liver disease. Two of the patients with primary biliary cirrhosis (13%) had clinical sicca syndrome. Our study demonstrates the following: (a) serum multiple nuclear dots antinuclear antibodies are not specific for liver disease because they can be observed in one third of patients with various immunological disorders without liver involvement, and (b) serum multiple nuclear dots antinuclear antibodies are not specific for PBC because they can also be observed in type 1 autoimmune chronic active hepatitis. Our results also suggest that patent sicca syndrome is abnormally present in patients with primary biliary cirrhosis and multiple nuclear dots antinuclear antibodies. (Hepatology 1992;16:127-131.)
Sodium Benzoate in the Treatment of Acute Hepatic Encephalopathy: A Double–Blind Randomized Trial
Authors: Sushma S. , Dasarathy S. , Tandon Rakesh K. , Jain Satish , Gupta Surya , Bhist Mahender S.
Published: March 2007

A prospective randomized double–blind study was conducted to evaluate the efficacy of sodium benzoate in the treatment of acute portal–systemic encephalopathy. Seventy–four consecutive patients with cirrhosis or surgical portasystemic anastamosis and hepatic encephalopathy of less than 7 days duration were randomized to receive lactulose (dose adjusted for 2 or 3 semiformed stools/day) or sodium benzoate (5 gm twice daily). Assessment of response included mental status, asterixis, arterial ammonia level, electroencephalogram and number–connection test. Each was given a score between 0 and 4+. A portal–systemic encephalopathy index was calculated with these scores. Visual, auditory and somatosensory evoked potentials and a battery of psychometric tests for intelligence and memory were also performed to assess improvement. Thirty–eight patients received sodium benzoate; 36 took lactulose. Thirty patients (80%) receiving sodium benzoate and 29 (81%) receiving lactulose recovered; the remaining patients died. Improvement in portal–systemic encephalopathy parameters occurred in both treatment groups and was similar (p > 0.1). Electroencephalogram and evoked potentials were not as helpful as mental status in assessing of recovery. Psychometric test scores remained abnormal after recovery of mental status (21 to 42 days) and were probably too sensitive for monitoring of these patients. The incidence of side effects was similar in the two treatment groups. The cost of lactulose for one course of therapy was 30 times that of sodium benzoate. We conclude that sodium benzoate is a safe and effective alternative to lactulose in the treatment of acute portasystemic encephalopathy. (Hepatology 1992;16:138-144.)
Association Between Heterozygous β1–Antitrypsin Deficiency and Genetic Hemochromatosis
Authors: Rabinovitz Mordechai , Gavaler Judith S. , Kelly Robert H. , Van Thiel David H.
Published: March 2007

Primary hemochromatosis is a genetically determined autosomal recessive disorder characterized by the excessive accumulation of body iron, most of which is deposited in the parenchymal cells of various organs.

β1–Antitrypsin deficiency is characterized among others by defective secretion of β1–antitrypsin from liver cells. Whereas the risk of cirrhosis is increased in homozygous patients (P1 ZZ) and possible in heterozygous patients (non–PI MM) as well, a greater risk for hepatocellular carcinoma has been suggested only in homozygous patients.

Because these two metabolic disorders are relatively common, it has been difficult to determine whether they are associated with each other. In this study, we tried to determine the relationship between these two disorders using the case material seen at the University of Pittsburgh during a 7–yr period.

We studied 15 patients with genetic hemochromatosis. β1–Antitrypsin quantitation and phenotyping were performed in each case using standard methods. The distribution of the various Pi phenotypes was compared with that found in a normal population and reported elsewhere. Odds ratio and χs2 tests were used to measure the relative risk and significance of association, respectively.

Eleven patients (73%) were found to be PI M and four (27%) were identified as being heterozygotes: three (20%) were PI MZ, and one (7%) was PI MS. The prevalence of the PI MS phenotype was similar to that in the general population (7% vs. 6.4%; NS). The PI MZ phenotype, however, was statistically more common in patients with hemochromatosis than in the general population (20% vs. 2.2%; p <0.004). The odds of having hemochromatosis among PI MZ patients is increased 11–fold (odds ratio = 11.25; 95% confidence interval: 1.95, 44.23). The mean serum level of β1 antitrypsin and the occurrence of hepatocellular carcinoma was similar in the patients with the PI M and non–PI M phenotypes.

It can be concluded that abnormal β1–antitrypsin alleles are seen more frequently in patients with genetic hemochromatosis than in the general population. Their coexistence may contribute to the earlier development of cirrhosis in some of these patients. However, it does not increase the risk for hepatocellular carcinoma despite the fact that each disorder alone is known to do so. (Hepatology 1992;16:145-148.)
Defective Methionine Metabolism in Cirrhosis: Relation to Severity of Liver Disease
Authors: Marchesini Giulio , Bugianesi Elisabetta , Bianchi Giampaolo , Fabbri Andrea , Marchi Elisabetta , Zoli Marco , Pisi Emilio
Published: March 2007

A block in the transsulfuration pathway has previously been suggested in cirrhosis on the basis of increased fasting methionine concentrations, decreased methionine elimination and low levels of methionine end products. To date, methionine elimination has never been studied under controlled steady–state conditions, and the relation of the severity of liver disease to impaired methionine metabolism has not been clarified. We measured methionine plasma clearance in 6 control subjects and in 12 patients with cirrhosis during steady–state conditions obtained by a primed, continuous methionine infusion. In the presence of high–normal fasting methionine concentrations (range = 14 to 69 μmol ± L-1 in controls and 26 to 151 μmol ± L-1 in cirrhotic patients), methionine plasma clearance was reduced in cirrhotic patients (2.25 ± S.D. 0.43 ml ± sec-1 vs. 2.86 ± S.D. 0.43 ml ± sec-1 in controls; p < 0.05), whereas methionine half–life was increased (282 ± 90 min vs. 187 ± 25 min in controls; p <0.05). Fasting methionine significantly correlated with methionine clearance. The infused methionine was not degraded to urea to any significant extent in cirrhotic patients, whereas a threefold increase in urinary urea nitrogen excretion rate was observed in controls. Similarly, taurine concentrations significantly increased both in plasma and in the urine in controls but not in cirrhotic patients. In cirrhotic patients methionine plasma clearance significantly correlated with galactose elimination capacity (r = 0.818) and with the Child–Pugh score (rs = -0.795). The study supports a major role of impaired liver cell function in the reduced metabolism of methionine and decreased formation of methionine end products that occur in cirrhosis. Impaired methionine metabolism is probably the basis for the hypermethioninemia of advanced cirrhosis. (Hepatology 1992;16:149-155.)
Plasma Levels of Brain Natriuretic Peptide in Patients With Cirrhosis
Authors: La Villa Giorgio , Romanelli Roberto Giulio , Raggi Vincenzo Casini , Tosti-Guerra Cristina , De Feo Maria Laura , Marra Fabio , Laffi Giacomo , Geñtilini Paolo
Published: March 2007

Plasma levels of brain natriuretic peptide, a recently identified cardiac hormone with natriuretic activity, were measured in 11 healthy subjects, 13 cirrhotic patients without ascites, 18 nonazotemic cirrhotic patients with ascites and 6 patients with cirrhosis, ascites and functional kidney failure. Plasma levels of brain natriuretic peptide were similar in healthy subjects and cirrhotic patients without ascites (5.56 ± 0.65 and 7.66 ± 0.68 fmol/ml, respectively). In contrast, cirrhotic patients with ascites, with and without functional kidney failure, had significantly higher plasma concentrations of brain natriuretic peptide (19.56 ± 1.37 and 16.00 ± 1.91 fmol/ml, respectively) than did healthy subjects and patients without ascites (p < 0.01); no significant difference was found between the two groups of cirrhotic patients with ascites with respect to this parameter. In the whole group of cirrhotic patients included in the study, brain natriuretic peptide level was directly correlated with the degree of impairment of liver and kidney function, plasma renin activity and plasma levels of aldosterone and atrial natriuretic peptide. The results of this study indicate that brain natriuretic peptide is increased in cirrhotic patients with ascites and suggest that sodium retention in cirrhosis is not due to deficiency of this novel cardiac hormone. (Hepatology 1992;16:156-161.)
Neurological Complications After Liver Retransplantation
Authors: Lopez Oscar L. , Estol Conrado , Colina Immaculada , Quiroga Jorge , Imvertarza Oscar C. , Van Thiel David H.
Published: March 2007

Postoperative neurological complications in 185 patients who underwent two or more orthotopic liver transplantations were reviewed. The most common neurological complications were alteration of mental status (84%), seizures (33%) and focal motor deficits (15%). The frequency of neurological complications after a second orthotopic liver transplantation was significantly greater than that after a single orthotopic liver transplantation. However, neurological complications were more frequent after a second orthotopic liver transplantation than after a third transplant. Significantly more neurological complications occurred in patients who did not survive a year than in those who did, regardless of the number of transplants they underwent. These findings indicate that the risk of neurological complications among patients with multiple orthotopic liver transplantations is greater in those who require a second transplant; this risk appears to diminish after a third transplant. Importantly, the presence of neurological complications is associated with increased post-orthotopic liver transplantation mortality rate. (Hepatology 1992;16:162-166.)
Hepatic Fibrosis in Rats Produced by Carbon Tetrachloride and Dimethylnitrosamine: Observations Suggesting Immunoassays of Serum for the 75 Fragment of Type Iv Collagen Are A More Sensitive Index of Liver Damage Than Immunoassays for the Nh2–Terminal Propeptide of Type Iii Procollagen
Authors: Ala-Kokko Leena , Günzler Volkmar , Hoek Jan B. , Rubin Emanuel , Prockop Darwin J.
Published: March 2007

Liver fibrosis was induced in rats both with carbon tetrachloride and dimethylnitrosamine. Assays were performed on steady–state levels of messenger RNAs in the liver for several collagens and basement membrane components. The results indicated marked increases in the steady–state levels of messenger RNA for type I collagen, type III collagen, type IV collagen and the B2 component of laminin. In the same animals, immunoasgays were performed for serum levels of the N–terminal propeptide of type 111 procollagen and the 75 fragment of type IV collagen. The results demonstrated an increase in the serum levels of 75 fragment that occurred early and closely paralleled the increase in the steady–state levels of messenger RNA for the al(IV) chain of type IV collagen. In contrast, no signiscant increase was seen in the serum levels of the N–propeptide of type 111 procollagen. The results suggest that immunoassays for 7s fragment of type IV collagen in serum are a more sensitive index for liver cell damage and fibrosis than assays for the N–propeptide of type III procollagen. The results suggest that greater attention should be paid to assays of 75 fragments in assessing hepatic fibrosis in man. (Hepatology 1992; 16: 167-172.)
Uptake of A Protein–Bound Polar Compound, Acetaminophen Sulfate, by Perfused Rat Liver
Authors: Goresky Carl A. , Pang Sandy K. , Schwab Andreas J. , Iii Ford Barker , Cherry Wendy F. , Bach Glen G.
Published: March 2007

The hepatocytic entry of acetaminophen sulfate conjugate was examined in the rat liver, perfused with red cells with and without albumin, by use of the multiple–indicator dilution technique. [3H]acetaminophen sulfate was injected into the portal vein in a bolus of blood containing51Cr–labeled red blood cells (a vascular reference), sucrose (a low–molecular–weight interstitial reference) or125I–labeled albumin (a high–molecular–weight interstitial reference, included when albumin was present), and the time courses of their outflow into the hepatic venous blood were observed. The [3H]acetaminophen sulfate, which binds partially to albumin, emerged between albumin and sucrose in the presence of albumin, precessed the upslope of the sucrose curve and showed a late low–in–magnitude tailing; the precession disappeared in the absence of albumin. Biliary excretion of [3H]acetaminophen sulfate was less than 1% of the dose. Quantitative evaluation with a barrier–limited, spacedistributed variable transit time model (including rapidly equilibrating albumin binding) accounted for the albumin effect on [3H]acetaminophen sulfate behavior and demonstrated a low liver cell permeability for the acetaminophen sulfate and a small interstitial binding space for its nonalbumin–bound fraction in excess of that for sucrose, which in the absence of albumin was of similar dimensions. (Hepatology 1992;16:173-190.)
Lipopolysaccharide Treatment of Rats Alters Antigen Expression and Oxidative Metabolism in Hepatic Macrophages and Endothelial Cells
Authors: Mc Closkey Thomas W. , Todaro Jeanine A. , Laskin Debra L.
Published: March 2007

Endothelial cells and macrophages are located within the hepatic sinusoids. These two cell types play an important role in the clearance of bacterially derived lipopolysaccharide from the portal circulation. Our laboratory has previously demonstrated that treatment of rats with lipopolysaccharide results in the accumulation of macrophages in the liver that display properties of activated mononuclear phagocytes. This study was designed to analyze the effects of lipopolysaccharide on hepatic endothelial cells. Female Sprague–Dawley rats were treated with 5 mg/kg of lipopolysaccharide. Macrophages and endothelial cells were isolated from the rats 48 hr later by in situ perfusion of the liver with collagenase and pronase followed by differential centrifugation and centrifugal elutriation. We found that lipopolysaccharide treatment of rats resulted in an increase in the number of both macrophages and endothelial cells recovered from the liver. Using specific monoclonal antibodies and flow cytometry, both macrophages and endothelial cells were found to express cell surface markers for Ia antigen, leukocyte common antigen, CD4 and the macrophage antigen, ED2. Macrophages expressed greater levels of these markers than endothelial cells. Flow cytometric analysis also revealed considerable subpopulation heterogeneity in the endothelial cells in antigen expression, physical characteristics and functional activity. Treatment of rats with lipopolysaccharide decreased expression of cell surface markers on the macrophages but not on the endothelial cells. This may be due to the distinct origin of these cells. To determine whether endothelial cells, like macrophages, were activated by lipopolysaccharide, we examined their ability to produce reactive oxygen intermediates. Using three different analytical methods, we found that both macrophages and endothelial cells produced reactive oxygen intermediates in response to 12–0–tetradecanoyl phorbol–13–acetate. This response was enhanced in cells from lipopolysaccharide–treated rats. Taken together, our data suggest that both endothelial cells and macrophages may be involved in the inflammatory response of the liver to lipopolysaccharide. (Hepatology 1992;16:191-203.)
Biglycan and Decorin Gene Expression in Normal and Fibrotic Rat Liver: Cellular Localization and Regulatory Factors
Authors: Meyer Dieter H. , Krull Nora , Dreher Kevin L. , Gressner Axel M.
Published: March 2007

The expression of genes encoding the core proteins of the novel small chondroitin/dermatan sulfate proteoglycans decorin and biglycan was studied in the livers of normal rats and in liver tissue during fibrogenesis induced by prolonged bile–duct ligation and thioacetamide poisoning. The cell types responsible for the expression of these transcripts and some key regulatory factors were identified. Both biglycan and decorin messenger RNAs were detected in normal liver tissue. Their relative abundance increased strongly during liver fibrogenesis, reaching highest levels in cirrhotic tissue 8 wk after common bile–duct ligation and after 12 wk of peroral thioacetamide administration, respectively. Specific proteoglycan transcripts were almost absent in hepatocytes from normal and regenerating liver, and only trace amounts were observed in freshly isolated and cultured Kupffer cells. Fat–storing cells clearly expressed both biglycan and decorin transcripts. The steady–state levels of their messenger RNAs increased threefold (biglycan) and fourfold (decorin) during primary culture. Myofibroblastlike cells (transformed fat–storing cells after the second passage) contained dramatically reduced levels of decorin messenger RNA and also lower levels of biglycan messenger RNA compared with primary cultures. These changes of core protein messenger RNA expression were not reflected by the synthesis rates of medium proteoglycans labeled with35S as Na2SO4, in particular that of medium chondroitin sulfate. Transiently acidified (but not native) conditioned media from Kupffer cells and myofibroblastlike cells and transforming growth factor–β1 enhanced the relative abundances of biglycan and decorin messenger RNAs up to five times in primary–cultured fat–storing cells. Biglycan and decorin in myofibroblastlike cells did not respond to these stimuli. Instead, transforming growth factor–α–conditioned and native conditioned media, both inefficient in primary cultures, were most effective in the elevation of the steady–state levels of these proteoglycan transcripts in transformed fat–storing cells. The data provide evidence for the expression of both biglycan and decorin in normal and fibrotic liver, which is a property of fat–storing cells and myofibroblastlike cells. Biglycan and decorin transcript levels are differentially regulated by transforming growth factor–β1, transforming growth factor–α, Kupffer cell-conditioned medium and myofibroblastlike cell-conditioned medium in fatstoring cells and their transformed countcrparts. (Hepatology 1992;16:204-216.)
Ethinylestradiol Increases Volume and Decreases Sinusoidal Membrane Surface in the Rat Liver: A Stereological Analysis
Authors: Hornstein Beat , Stammler Lukas , Bianchi Leonardo , Landmann Lukas
Published: March 2007

Structural alterations of liver parenchyma caused by ethinylestradiol, a synthetic estrogen known to induce cholestasis and to act as a tumor promoter factor, were investigated. Male rats treated with 17α–ethinylestradiol (5 mg/kg body weight for 5 days) were compared with controls (n = 5 each). After perfusion fixation and systematic random sampling, paraffin sections, semithin sections and thin sections were examined observing standard stereological techniques. Ethinylestradiol treatment induced an increase in liver volume by 65% (p < 0.001), which was caused more by hypertrophy (volume of singular hepatocyte + 35%, p < 0.001) than by hyperplasia (number of hepatocytes + 23%, p < 0.001). A decrease in sinusoidal membrane surface density (- 43%, p < 0.005) associated with a decrease in sinusoidal microvillar volume density (- 50%, p < 0.005) were both compensated for by the increase in liver volume. No canalicular alterations were observed. Thus changes in hepatocytes detectable with stereological techniques affect the sinusoidal pole where decreased sinusoidal membrane surface is associated with or reflects a substantial loss of membrane phospholipids. The increased liver volume may constitute an adaptive response compensating for the relative decrease in sinusoidal membrane surface and displays characteristics comparable to those of preneoplastic hepatocytes. (Hepatology 1992;16:217-223.)
Endotoxins Inhibit Endocytotic Catabolism of Low–Density Lipoproteins in Hep G2 Cells
Authors: Liao Wei , Florén Claes-Henrik
Published: March 2007

The effects of endotoxins on the uptake and degradation of low–density lipoproteins in Hep G2, a welldifferentiated human hepatoma cell line, were studied. The results showed that incubation of Hep G2 cells with125I–labeled low–density lipoprotein in the presence of endotoxins caused decreased uptake and degradation of125I–labeled low–density lipoprotein. The inhibitory effects of endotoxins on the uptake and degradation of125I–labeled low–density lipoprotein were dose and time dependent. With a monoclonal low–density lipoprotein receptor antibody, it was found that endotoxins interfered with both low–density lipoprotein receptor-mediated and non–low–density lipoprotein receptor-mediated uptake. If, however, the cells were pretreated with endotoxins for 1 or 24 hr and then incubated with new medium without endotoxins, no inhibitory effect on the subsequent uptake and degradation of125I–labeled low–density lipoprotein occurred. Endotoxins had no toxic effects on Hep G2 cells as judged by [3H]thymidine incorporation and by determination of cell growth. Also, endotoxins did not under our experimental conditions induce oxidative modification of low–density lipoprotein. Furthermore, reisolated low–density lipoprotein that had previously been incubated with endotoxin was catabolized to a lower extent by Hep G2 cells than was control lowdensity lipoprotein. We speculate that the inhibitory effect of endotoxins on cellular low–density lipoprotein catabolism is due to the formation of endotoxin-lowdensity lipoprotein complexes, which interfere with the binding of low–density lipoprotein to the cell surface. (Hepatology 1992;16:224-231.)
Urea and Protein Synthesis in Cold–Preserved Isolated Rat Hepatocytes
Authors: Vreugdenhil Paul K. , Marsh Diane C. , Belzer Folkert O. , Southard James H.
Published: March 2007

We used an isolated–hepatocyte model to study how hypothermic storage (simulating liver preservation) affects metabolism after prolonged preservation. Rat hepatocytes were stored in the University of Wisconsin solution for up to 72 hr. After each day of storage, protein synthesis, urea synthesis, ATP content and lactate dehydrogenase release were determined in rewarmed (37° C) and oxygenated hepatocytes. Protein synthesis ([3H]–leucine incorporation into protein) was depressed by 16% ± 4%, 54% ± 6% and 69% 4% after 24 hr, 48 hr and 72 hr, respectively. Urea synthesis, ATP synthesis and lactate dehydrogenase release were similar to those in control hepatocytes (no preservation). Fasting of the rats before isolation of hepatocytes caused more rapid loss of protein–synthetis capabilities (59% in 24 hr) with no significant loss of lactate dehydrogenase, urea synthesis or ATP synthesis. Hepatocyte viability (lactate dehydrogenase release) as judged by membrane permeability, ATP synthesis and potassium content can be maintained after up to 6 days of cold storage. However, protein synthesis is depressed after only 48 hr of cold storage. Thus hypothermic storage of the liver causes a change in the metabolic capabilities of the hepatocytes, and the timing of the loss of protein synthesis is similar to the limits of successful cold storage of the whole liver (48 hr). Thus a limit to long–term storage of the liver may be related to loss of protein synthesis. In liver transplantation, one indication of poor preservation is a decrease in serum albumin and clotting factors with increased tissue edema and bleeding diathesis. Livers from fasted animals (or donors) may be more sensitive to preservation injury because of the more rapid loss of protein synthesis. The mechanism for loss of proteinsynthesis capabilities is not related to a decrease in ATP but may be due to changes in cellular content of RNA or DNA. Preservation of the loss of the capability of the hepatocytes to synthesize protein may be a key to obtaining excellent–quality long–term liver preservation. (Hepatology 1992;16:241-246.)
Transforming Growth Factor-β: the Elusive Hepatic Chalone?
Authors: Strain Alastair J.
Published: March 2007

Incubation of fetal rat hepatocytes (FRH) with transforming growth factor β1 (TGF–β1) resulted in growth arrest and a biphasic effect on epidermal growth factor (EGF) receptor. After 2 h of exposure, EGF receptor (EGFR) was reduced by 43%. From 6 to 24 h, TGF–β1 exposure resulted in progressive increase in EGFR up to 74% over control. The increased binding was due to increase in high affinity EGF binding sites. FRH grown in medium containing EGF exhibited down–regulated EGFR with loss of high affinity EGF binding sites. With TGF–β1 exposure, high affinity EGFR was not down–regulated by EGF. Since downregulation of EGFR involves internalization, the kinetics of EGF receptor–mediated endocytosis were examined. In TGF–β1 exposed FRH, EGF endocytosis was inhibited, with a reduction in the first order rate constant for the process from 0.078 to 0.043 min-1. Despite inhibition of growth, receptor downregulation, and EGF endocytosis after TGF–β1 exposure, EGF–induced receptor autophosphorylation was preserved as demonstrated by [32P]phosphatelabeling of immunoprecipitated EGFR. These observations provide direct evidence that TGF–β1 regulates growth of fetal cells. Further, they suggest that TGF–β1 regulates endocytosis of EGF and possibly of other ligands.