bluuebunny/crossref_metadata_2025 huggingface dataset:
Bilirubin Mono- and diglucuronide formation by human liver In vitro : Assay by high-pressure liquid chromatography
Authors: Chowdhury Jayanta Roy , Chowdhury Namita Roy , Wu George , Shouval Rivka , Arias Irwin M.
Published: March 2007

Bilirubin diglucuronide, the major pigment in human bile is formed in two steps. Bilirubin is converted to bilirubin monoglucuronide by transfer of the glucuronosyl moiety of uridine diphosphoglucuronic acid catalyzed by the microsomal enzyme, uridine diphosphoglucuronate glucuronosyl transferase (UDP glucuronyl transferase, EC 2.4.1.17). Bilirubin monoglucuronide is converted to bilirubin diglucuronide in vitro by two enzymatic mechanisms: (a) UDP glucuronyl transferase-mediated transfer of a second mole of glucuronic acid form UDP-glucuronic acid to bilirubin monoglucuronide; (b) dismutation of 2 moles of bilirubin monoglucuronide to 1 mole of bilirubin diglucuronide and 1 mole of unconjugated bilirubin, catalyzed by bilirubin monoglucuronide dismutase (bilirubin glucuronoside glucuronosyl transferase EC 2.4.1.95). Assay methods for the three enzymatic mechanisms in human liver homogenate by high-pressure liquid chromatography analysis of underivatized bilirubin tetrapyrroles have been developed. UDP glucuronyl transferase was activated in five human liver homogenates with digitonin, Triton X-100, or UDP-N-acetylglucosamine. Greatest activation was observed with Triton X-100. The pH optimum for conversion of bilirubin to bilirubin monoglucuronide was 7.4, and UDP glucuronyl transferase activity was 625 ± 51 nmoles per 20 min per gm liver. At high initial bilirubin concentrations (342 μM), the product of UDP glucuronyl transferase assay with bilirubin as substrate was predominantly bilirubin monoglucuronide. At lower initial bilirubin concentrations (6.5 to 34 μM), up to 15% bilirubin diglucuronide was formed. Glucuronyl transferase-mediated UDP glucuronic acid-dependent conversion of bilirubin monoglucuronide to diglucuronide was assayed using UDP-14-C-glucuronic acid. The pH optimum was 7.4, and the rate was 21 ± 7 nmoles per gm liver per 20 min. The rate of bilirubin diglucuronide formation by enzymatic dismutation of bilirubin monoglucuronide was 470 ± 112 nmoles per gm liver per min. The pH optimum was 6.6. The products of enzymatic dismutation were of the IXα configuration.
Effects of Dexamethasone on Albumin and Collagen Gene Expression in Primary Cultures of Adult Rat Hepatocytes
Authors: Jefferson Douglas M. , Reid Lola M. , Giambrone Marie-Adele , Shafritz David A. , Zern Mark A.
Published: March 2007

To further our studies on collagen gene expression, we have evaluated the molecular basis for the finding that steroids decrease collagen synthesis in cultured hepatocytes. We studied the effects of dexamethasone on primary cultures of adult rat hepatocytes grown on tissue culture plastic in either serum–supplemented medium or a serum–free hormonally defined medium. Cells were plated and allowed to attach for 24 hr in a mixture of serum–supplemented medium + hormonally defined medium. Cultures were then fed every 24 hr for 4 days under 1 of 4 conditions: serum–supplemented medium, serum–supplemented medium + dexamethasone, hormonally defined medium or hormonally defined medium + dexamethasone. On the fifth day, RNA was extracted. Dexamethasone did not affect the amount of RNA isolated; nor did it influence the quantitative translation of the mRNA in the rabbit reticulocyte lysate mRNA–dependent system. Employing hybridization analysis, dexamethasone resulted in increased albumin mRNA content in hepatocytes grown in serum–supplemented medium but had no affect on hormonally defined medium, and decreased type I in collagen mRNA content in cells grown in either serum–supplemented medium or hormonally defined medium. In cells cultured in hormonally defined medium, the β–actin and procollagen mRNA levels were lower than those in serum–supplemented medium, but albumin mRNA levels were higher, and in fact equivalent to thosein vivo.β–Actin mRNA levels were not affected by dexamethasone in either serum–supplemented medium or hormonally defined medium. These results suggest that hormonally defined medium improves the expression of tissue–specific functions in hepatocytes, and dexamethasone reduces Type I collagen mRNA content in hepatocytes as well as mesenchymal cells. It is presently not clear whether the changes in albumin and collagen steady state mRNA levels are due to transcriptional and/or post–transcriptional controls.
Reversal of Ethanol and Indomethacin–Induced Suppression of Hepatic Dna Synthesis by 16,16–Dimethyl Prostaglandin E2
Authors: McNeil Gloria E. , Chen Thomas S. , Leevy Carroll M.
Published: March 2007

Investigations were undertaken to determine effectiveness of 16,16–dimethyl prostaglandin E2 (dmPGE2) in overcoming the suppressive effects of ethanol and/or indomethacin on hepatic DNA synthesis. Adult litter mate Sprague–Dawley rats were subjected to sham operation or partial hepatectomy. Immediately after partial hepatectomy, and at 8–hr intervals for 24 hr, the rats were given: (a) ethanol with and without dmPGE2 or (b) indomethacin with and without ethanol and/or dmPGE2. DmPGE2 produced a significant increase in DNA synthesis in sham–operated (p < 0.001) and untreated partially hepatectomized animals (p < 0.025). Ethanol and indomethacin caused a 6– and 18–fold reduction, respectively, in hepatic DNA synthesis following partial hepatectomy. DmPGE2 overcame the inhibitory effect of ethanol (p < 0.005) and indomethacin (p < 0.0005) in partially hepatectomized animals. Mitoses were decreased concomitantly with ethanol and/or indomethacin–induced reduction in DNA synthesis and increased with administration of dmPGE2.

It is concluded that dmPGE2 increases hepatic DNA synthesis and regeneration in normal rat liver and overcomes their inhibition when ethanol and/or indomethacin is given after partial hepatectomy. Timing of dmPGEz administration is crucial. When given 30 min before ethanol, it completely inhibits suppression of regenerative activity; omission of this “priming” dmPGE2 dose results in only 44% of DNA synthesis obtained in control animals.
The Diagnosis of Bacterial Peritonitis: Comparison of Ph, Lactate Concentration and Leukocyte Count
Authors: Garcia-Tsao Guadalupe , Conn Harold O. , Lerner Emanuel
Published: March 2007

It has been suggested that the hydrogen ion and lactate concentrations may be superior to the polymorphonuclear cell count (PMN) in ascitic fluid, in the diagnosis of bacterial peritonitis (BP). In order to compare the diagnostic accuracy of ascitic fluid measurements of pH, lactate, glucose and the PMN in BP, we analyzed the ascitic fluids of 70 consecutive patients in whom pH, lactate, glucose and the PMN count were measured in ascitic fluid and arterial blood. Fifty–one were cirrhotic patients with uninfected ascites, 14 had BP, one tuberculous peritonitis, two ascites secondary to peritoneal metastases and two with neoplastic liver involvement but without peritoneal metastases. Statistically, highly significant differences between patients with uninfected ascitic fluid and BP were observed for ascitic fluid PMN (122 vs. 2,686 per cu mm), ascitic fluid pH (7.45 vs. 7.24), arterial–ascitic fluid pH gradient (0.02 vs. 0.22), arterial lactate (12 vs. 25 mg per dl), ascitic fluid lactate (15 vs. 45 mg per dl) and arterial–ascitic fluid lactate gradient (-3 vs. -20 mg per dl). The most reliable diagnostic cutoff levels were determined for each of the parameters: PMN > 500 per cu mm; ascitic fluid pH < 7.35; arterial–ascitic fluid pH gradient > 0.10; ascitic fluid lactate > 25 mg per dl; arterial–ascitic fluid lactate gradient < -20 mg per dl; ascitic fluid glucose < 60 mg per dl; arterial–ascitic fluid glucose gradient > 60 mg per dl. The highest sensitivity was demonstrated by the PMN count (86%), which also had the highest negative predictive value (96%). Very high specificity but lower sensitivity was demonstrated for ascitic fluid pH, arterial–ascitic fluid pH gradient, ascitic fluid lactate and the arterial–ascitic fluid lactate gradient. Diagnostic sensitivity increased when either of two parameters were required to establish the diagnosis. We believe that the most reliable combination for clinical purposes is an ascitic fluid PMN count > 500 per cu mm and/or an arterial–ascitic fluid pH gradient > 0.10. This investigation shows that an elevated PMN count in ascitic fluid is a reliable index of BP. A decreased ascitic fluid pH (<7.35) or an increased arterial–ascitic fluid pH gradient (>0.10) are about equally reliable. These tests complement each other's diagnostic ability. An ascitic fluid PMN count > 500 per cu mm and/or an arterial–ascitic fluid pH gradient greater than 0.10 are almost always diagnostic of BP, and the normality of both tests virtually excludes that diagnosis.
Liver Plasma Membrane: the Source of High Molecular Weight Alkaline Phosphatase in Human Serum
Authors: De Broe Marc E. , Roels Frank , Nouwen Etienne J. , Claeys Lutgarde , Wieme Roger J.
Published: March 2007

This study presents biochemical, histochemical, morphological and immunological evidence that part of the high molecular weight alkaline phosphatase observed in the serum of patients with liver disease and particularly in cases of intrahepatic cholestasis or focal–, extrahepatic obstruction originates from the liver plasma membrane.

The high molecular weight protein alkaline phosphatase complex contains several plasma membrane enzymes and behaves like a plasma membrane fragment after isopycnic density gradient ultracentrifugation in sucrose, cesium chloride and metrizamide. Electron microscopic examination revealed a triple–layered vesicle which retained alkaline phosphatase activity. Incubation of human liver cells with anti–serum against purified high molecular weight multienzyme complex resulted in fixation of antibodies on the plasma membrane as shown by positive plasma membrane fluorescence. These plasma membrane fragments in the serum are not of biliary origin.
S Ublobular C Ompartmentation O F P Harmacologic E Vents (Scope): Metabolic Fluxes in Periportal and Pericentral Regions of the Liver Lobule
Authors: Thurman Ronald G. , Kauffman Frederick C.
Published: March 2007

New techniques have been developed employing microlight guides and miniature O2 electrodes which permit metabolic events to be studied noninvasively in periportal and pericentral zones of the liver lobule. These events include O2 uptake, fat and carbohydrate metabolism, monooxygen–ation and glucuronidation. The lobular distribution of maximal enzyme activities measured by immunohistochemical or microchemical techniques does not always correlate with metabolic flux rates as measured in periportal and pericentral regions with the new noninvasive methods. The region of the liver lobule exhibiting highest metabolic flux rates can be shifted to another region of the lobule by changing the direction of flow from anterograde to retrograde. These data are consistent with the hypothesis that many metabolic pathways (e.g., oxygen, carbohydrate and fat metabolism which are under dynamic short–term regulation) operate below maximal velocity in intact hepatocytes.
Lack Of In Vivo Activation of the Interferon System in Hbsag–Positive Chronic Active Hepatitis
Authors: Poitrine Alain , Chousterman Suzanne , Chousterman Michel , Naveau Sylvie , Thang Ming Nguy , Chaput Jean-Claude
Published: March 2007

The in vivo activation state of the interferon system was biochemically evaluated in patients with HBsAg–positive liver disease by assaying the interferon–induced enzyme, 2′5′–oligoadenylate synthetase, in peripheral blood mononuclear cells. All patients with chronic active hepatitis had normal levels of enzyme activity. Increased values were found in 77% of patients with acute hepatitis, 50% of those with chronic persistent hepatitis and 54% chronic healthy carriers. These results provide evidence for lack of activation of the interferon system in HBsAg–positive chronic active hepatitis and support the hypothesis that an in vivo defective interferon response may aid in development of chronic active hepatitis.
Therapeutic Efficacy of Glucan in A Murine Model of Hepatic Metastatic Disease
Authors: Williams David L. , Sherwood Edward R. , McNamee Rose B. , Jones Ernest L. , Di Luzio Nicholas R.
Published: March 2007

Glucan, a particulate β–1,3–polyglucose immunomodulator, was evaluated for its ability to modify hepatic metastases and survival in mice with reticulum cell sarcoma. Sarcoma M5076 cells were injected subcutaneously (1 × 105 cells) into syngeneic C57BL/6J male mice. On Day 20, histopathological studies indicated the presence of hepatic micrometastases. At this time, glucan (0.45 mg per mouse) or dextrose was administered intravenously. Therapy was continued at 3–day intervals up to Day 50. By Day 36 postchallenge, the glucan–treated group, when compared to the control group, showed a marked decrease in hepatic metastases, both grossly and histopathologically. A significant inhibition in the growth of the primary tumor also occurred. Plasma clearance of bromosulfophthalein measured on Day 36, denoted that glucan therapy maintained hepatic parenchymal cell functional integrity, while a 4–fold impairment in bromosulfopthalein removal was observed in control mice. Glucan–treated mice showed a 28% (p < 0.05) long–term survival. In contrast, control mice showed a 100% mortality by Day 42 postchallenge. Studies to evaluate the mechanism of the anti–metastatic action of glucan indicated that 8 days after glucan administration, isolated hepatic macrophages were significantly more cytotoxic to sarcoma cells in vitro than were normal Kupffer cells. At this time, the cytotoxic activity of peritoneal and splenic macrophages from glucan–treated mice were unaltered. Additionally, co–incubation of particulate glucan with diverse populations of normal or tumor cells in vitro indicated that glucan exerted a direct cytostatic effect on sarcoma and melanoma cells and, in contrast, had a proliferative effect on normal spleen and bone marrow cells. These studies denote that glucan, administered therapeutically will: (i) significantly inhibit hepatic metastases; (ii) inhibit the growth of the primary tumor, and (iii) enhance long–term survival possibly by increased Kupffer cell tumoricidal activity as well as a direct cytostatic effect of glucan on sarcoma cells.
The Effect of Concentration on Hepatic Transport of Exogenous Epidermal Growth Factor
Authors: Burwen Susan Jo , Barker Mary E. , Goldman Ira S. , Jones Albert L.
Published: March 2007

Epidermal growth factor (EGF), taken up by rat liver hepatocytes, is primarily transported to the lysosomes and degraded. However, a small but significant percentage of endocytosed EGF is transported by a nonlysosomal pathway and is secreted intact into bile. There is no information as to the mechanisms that regulate the selection of transport pathway and thereby determine the different metabolic fates for EGF. The experiments reported here were undertaken to determine whether the amount of exogenous EGF administered to the liver (the transport load) might affect the selection of the transport pathway. If “excess” EGF, exceeding some as yet undetermined threshold, is preferentially transported by the lysosomal pathway, then the proportion of degraded EGF secreted into bile should increase as a function of the amount of EGF administered. 125I–EGF (3 to 175 ng) was injected into rat portal veins, and bile samples were collected via cannula. The radioactivity secreted into bile was measured, and the bile samples were immunoprecipitated with anti–EGF antiserum. The proportion of intact vs. degraded EGF in bile was determined by the percentage of immunoprecipitable radioactivity. Regardless of the amount of EGF injected, the pattern of its secretion was unaltered. The percentage of immunoprecipitable EGF in bile was the same for all doses. Therefore, the amount of EGF that was degraded did not change as a function of EGF concentration, implying that the lysosomal pathway was not preferentially utilized as the transport load increased. In conclusion, transport load does not appear to be a regulatory mechanism in the selection of transport pathway utilized by EGF.
Acetaminophen–Induced Hepatotoxic Congestion in Mice
Authors: Walker Robin M. , Racz William J. , McElligott Francis T.
Published: March 2007

Acetaminophen–induced (750 mg per kg p.o.) hepatotoxicity in mice is characterized by hepatomegaly and massive centrilobular congestion which precede the appearance of necrosis. The vascular changes are correlated with the morphologic features using liver hemoglobin content to quantitate erythrocyte sequestration, and hematocrit measurements and 125I–albumin injections to determine plasma and blood volume. The initial increase in liver size was a result of plasma accumulation due to endocytic vacuolation of hepatocytes and Disse space enlargement in centrilobular regions. Further increases in liver size after 3 hr were a consequence of erythrocyte and additional plasma sequestration within the damaged liver. These events occurred without any increase in intrahepatic or portal venous pressure. Hepatic hemoglobin and plasma levels increased 10– and 5–fold, respectively, by 4.5 to 6 hr after administration of acetaminophen. There are two major consequences of acetaminophen–induced hepatotoxic congestion. First, blood and plasma volumes fell significantly, and we suggest that hypovolemic shock contributes to early mortality after acetaminophen. Second, impaired circulation within the congested liver, as manifested by reduced 125I–albumin entry into the liver when 125I–albumin was injected after congestion had developed, probably aggravates the initial injury. Early lesions were always evenly distributed around central veins. However, the pattern of damage at 24 hr could be variable. Occasional large confluent areas of necrosis were always congested, which is consistent with the concept that secondary ischemic damage can develop. Congestion and hypovolemia are reversible and can be largely prevented by administration of the protective compound N–acetylcysteine (1,200 mg per kg p.o.) 3 hr after acetaminophen.
Aldehyde Dehydrogenase in Alcoholic Subjects
Authors: Palmer Kelvin R. , Jenkins William J.
Published: March 2007

Hepatic aldehyde dehydrogenase activity is depressed in alcoholic liver disease and may account for the observation that alcoholics develop high blood acetaldehyde concentrations following ethanol. To determine whether this is a specific defect in alcoholics, aldehyde dehydrogenase was studied in liver tissue obtained from three groups of subjects. Group I comprised 30 patients with alcoholic liver disease, Group II consisted of eight subjects with liver disease unrelated to alcohol abuse and Group III was a control group of 10 individuals with no significant liver disease. Mean hepatic aldehyde dehydrogenase activity was significantly lower in Group I than in Groups II or III [4.9 ± 0.6 (mean ± S.E.), compared to 10.2 ± 1.8 and 12.4 ± 1.1 nmoles of acetaldehyde oxidized per min ± mg of protein, respectively]. Aldehyde dehydrogenase activity in Group II was relatively well maintained.

Aldehyde dehydrogenase activity was found in cytosolic and mitochondrial fractions of liver homogenates. In alcoholic subjects, cytosolic aldehyde dehydrogenase activity was not more depressed than was mitochondrial aldehyde dehydrogenase. Isoelectric focusing demonstrated a single mitochondrial isoenzyme and a single cytosolic isoenzyme in most cases in Group III. In contrast, multiple cytosolic isoenzymes were consistently found in liver tissue from Group I subjects.

These findings suggest that depressed aldehyde dehydrogenase activity in alcoholic subjects is not a consequence of liver disease.
Viral Hepatitis in Colombia: A Study of the “Hepatitis of the Sierra Nevada De Santa Marta”
Authors: Ljunggren Karin E. , Patarroyo Manuel E. , Engle Ronald , Purcell Robert H. , Gerin John L.
Published: March 2007

The prevalences of hepatitis B virus (HBV), hepatitis delta virus and hepatitis A virus infections were studied in two regions of Colombia. In Bogota, 10 of 53 patients with acute hepatitis were HBsAg positive and three of these were hepatitis D antigen positive. Hepatitis A virus was the major cause of acute hepatitis in this group. In 366 healthy controls from Bogota, 1.6% were HBsAg positive and 7.1% had at least one marker of HBV infection. In northern Colombia, individuals from three villages with outbreaks of the fulminant “hepatitis of the Sierra Nevada de Santa Marta” were tested. The prevalences of HBsAg (1.8 to 23%) and HBV infection (35 to 93%) were generally high and varied from village to village; 60% of the HBsAg carriers in one village were positive for antibody to hepatitis D antigen, and two individuals in the outbreak area had circulating hepatitis D antigen. The findings suggest that HBV and the associated hepatitis delta virus are etiologic factors in the “hepatitis of the Sierra Nevada de Santa Marta”.
Tubular Dysfunction in the Deeply Jaundiced Patient With Hepatorenal Syndrome
Authors: Rector William G. , Kanel Gary C. , Rakela Jorge , Reynolds Telfer B.
Published: March 2007

We examined β2–microglobulin (B2MG) excretion, an index of tubular function, in patients with hepatorenal syndrome, in whom tubular function is generally regarded as normal. Urine B2MG was significantly higher in these patients than in control patients with normal serum creatinine concentration. Patients with high urine B2MG concentration had markedly higher serum bilirubin than did patients with normal values (31 ± 3 vs. 10 ± 8 mg%, p < 0.001), whereas prothrombin activity, serum albumin and serum B2MG concentration were similar. A “threshold” serum bilirubin concentration of about 23 mg% differentiated patients with normal and high urine B2MG values. Renal morphology at autopsy was unremarkable in both groups. Tubular dysfunction, manifested by increased urinary excretion of B2MG, occurs in patients with hepatorenal syndrome and deep jaundice. This measurement cannot, therefore, be used to make a diagnosis of acute tubular injury, as due to aminoglycosides, in such patients.
Age–Related Changes in the Endocytic Capacity of Rat Liver Kupffer and Endothelial Cells
Authors: Brouwer Adriaan , Barelds Roel J. , Knook Dick L.
Published: March 2007

There are many indications that the functional capacity of the reticuloendothelial system (RES) declines with age. The aim of this study was to investigate the cellular basis of age–related changes in the clearance function of the RES. The experiments were focused mainly on Kupffer and endothelial cells of the liver which represent a major part of the RES and are primarily responsible for clearance of colloidal material from the circulation. The clearance capacity of the RES was tested clinically and experimentally by intravenous injection of colloids, such as radiolabeled heataggregated colloidal albumin.

Age–related changes in the endocytosis of 125I–labeled colloidal albumin (CA) in rats were determined by clearance and organ distribution of different doses of intravenously injected CA, uptake of CA by Kupffer and endothelial liver cells in vivo as determined after isolation of the cells from injected rats and kinetic studies on CA uptake by Kupffer cells in culture.

The results show that, at a low dose, the clearance of CA is primarily determined by liver blood flow. At a higher saturating dose, plasma clearance and uptake by the liver are not significantly decreased with age. Endocytosis by endothelial cells, which accounts for about 60% of that of the whole liver, is also unchanged with age. In contrast, a significant decrease in endocytic capacity was observed for Kupffer cells in vivo. This age–related functional decline was also observed in Kupffer cells which were isolated from rats of different ages and maintained in culture. It is concluded that the overall capacity of the liver to clear the circulation of colloidal material is not necessarily affected by age. However, the Kupffer cell–specific decrease in endocytic capacity with advancing age may be important in the increased sensitivity to agents which are exclusively removed by Kupffer cells.
Hepatic Clearance of Rat Liver Aspartate Aminotransferase Isozymes: Evidence for Endocytotic Uptake Via Different Binding Sites on Sinusoidal Liver Cells
Authors: Horiuchi Seikoh , Kamimoto Yukio , Morino Yoshimasa
Published: March 2007

Rat liver aspartate aminotransferase (AAT) (EC 2.6.1.1) exists in two isozymic forms, cytosolic (c–AAT) and mitochondrial (m–AAT). The previous study (Kamimoto, Y. et al., Hepatology an accompanying paper in this issue) demonstrated that these isozymes were cleared from blood at different half–lives via adsorptive endocytosis by sinusoidal liver cells. To understand the cellular mechanism for the differential uptake of the isozymes, we have further studied in vivo uptake of 125I–labeled AAT isozymes by sinusoidal cells. The results indicated that the uptake of the isozymes occurred via a typical endocytotic pathway: the initial binding, internalization and subsequent degradation in the lysosomes. Quantitation of the isozymes bound to the cell surface prior to internalization either by binding at 4°C or by a combined use of anti–AAT antibody and 125I–protein A at 37°C revealed that the differential plasma clearance of AAT isozymes could be attributable to the isozymic difference in capacity of surface membranes to bind the isozymes. The uptake of 125I–c–AAT was inhibited by unlabeled c–AAT more significantly than by m–AAT, but not by other ligands known to be taken up by sinusoidal cells via receptor–mediated pathways. Similarly, the uptake of 125I–m–AAT was inhibited predominantly by unlabeled m–AAT. Similar ligand specificity was also demonstrated in the binding study at 4°C. The binding of 125I–m–AAT and c–AAT followed saturation kinetics with an apparent Kd of 1.3 × 10-6
M and 1.7 × 10-6
M, respectively.

These findings indicate that differential uptake of AAT isozymes results from the presence on the surface membrane of two binding sites with a definite specificity for each isozyme.
Portal Pressure, Presence of Gastroesophageal Varices and Variceal Bleeding
Authors: Garcia-Tsao Guadalupe , Groszmann Roberto J. , Fisher Rosemarie L. , Conn Harold O. , Atterbury Colin E. , Glickman Morton
Published: March 2007

This study was performed to examine the relationships between portal pressure measurements and the presence of esophagogastric varices, the size of varices and the occurrence of hemorrhage from varices in 93 patients with alcoholic cirrhosis, using standardized measurements of portal pressure by hepatic vein catheterization.

The mean hepatic vein pressure gradient (HVPG) was significantly higher in 49 patients who had bled from varices than in 44 cirrhotic patients who had not (20.4 ± 5.1 vs. 16.0 ° 5. 2; p < 0.001). None of the 49 patients who had bled from varices had an HVPG <12 mm Hg. Among the 87 patients who had been examined by endoscopy for varices, all 72 with varices had an HVPG > 12 mm Hg. Six of 15 cirrhotic patients without varices had HVPG < 12 mm Hg.

The mean HVPG in the 15 patients without varices (15.1 ± 6.8 mm Hg) was lower than the 72 patients with varices (19.3 ± 4.8 mm Hg; p < 0.01).

Of the 72 patients with varices, 40 had large varices, 28 had small varices, and in four patients variceal size coukt not be assessed adequately. The mean HVPG was similar in the patients with large or small varices (19.8 ± 4.8 vs. 18.3 ± 5.0 mm Hg; p < 0.10).

There was a positive relationship between the presence of large varices and the occurrence of bleeding from varices. Thirty–three of the 46 patients who had bled from varices had large varices (72%) compared to 7 of the 22 who had not bled from varices (32%) (p < 0.01).

The mean HVPG was similar in groups with large varices who had bled (20.3 ± 4.9) and in the group with small varices who had bled (20.2 ± 6.2 mm Hg) (p > 0.10). The mean HVPG in the groups of patients with large varices who had not bled was similar to those with small varices who had not bled (17.3 ± 3.1 vs. 16.7 ± 3.2 mm Hg) (p > 0.10). In both groups, the pressure was lower in those who had not bled.

We confirm previous observations that an HVPG > 12 mm Hg is necessary for the occurrence of variceal hemorrhage. We note in addition that this pressure gradient is necessary for the appearance of gastroesophageal varices. Elevated portal pressure plays a major role in the development of esophageal varices, but other factors contribute to the precipitation of hemorrhage from varices. All of these factors, which include size of the varix, thickness of the wall and transmural pressure are integrated in the wall stress formula, which is based on the LaPlace formula. Risk factors are multiple and variable and may interact in the individual patient to precipitate variceal hemorrhage.
Immunofluorescent Determination of the Lobular Distribution of A Constitutive Form of Hepatic Microsomal Cytochrome P–450
Authors: Moody David E. , Taylor Lorna A. , Smuckler Edward A.
Published: March 2007

We have used an immunohistochemical approach to study the lobular distribution of constitutive liver microsomal cytochrome P–450. Cytochrome P–450 isolated (10.3 nmoles per mg protein) from hepatic microsomes from untreated, mature male Sprague–Dawley rats was used to produce antisera in rabbits. The IgG fraction produced single precipitin lines of identity with liver microsomes after double immunodiffusion, precipitated 80% of the total microsomal cytochrome P–450 and inhibited three cytochrome P–450–dependent enzyme activities. By these criteria, the IgG appeared to be specific for a constitutive form (or immunochemically related family) of liver microsomal cytochrome P–450.

The pattern of fluorescence after indirect immunofluorescent labeling of liver sections depended on the route of tissue preparation and the concentration of primary antibody. In frozen sections, the labeling was uniform throughout the lobule, whereas in “antigen–depleted” paraffin–embedded sections it was heaviest in the centrilobular and midzohal regions. Increasing the concentration of primary antibody to 500 μg per ml inhibited the centrilobular labeling in frozen sections in a concentration–dependent manner. When specific isozymes of cytochrome P–450 were induced with phenobarbital or 3–methylcholanthrene, the constitutive cytochrome P–450 was localized predominantly in the periportal region. Decreases in cytochrome P–450 in rats treated with carbon tetrachloride or 1,2–dibromo–3–chloropropane were associated with antigen loss only in necrotic cells. Regional differences in the loss of antigen in paraffin sections and the inhibition of fluorescence in frozen sections establish that the lobular distribution of constitutive hepatic microsomal cytochrome P–450 is qualitatively heterogeneous and may be altered during hepatocellular responses to chemical treatment.
Biliary and Urinary Excretion of Sulfated, Glucuronidated and Tetrahydroxylated Bile Acids in Cirrhotic Patients
Authors: Stiehl Adolf , Raedsch Richard , Rudolph Gerda , Gundert-Remy Ursula , Senn Martin
Published: March 2007

In patients with hepatobiliary diseases, considerable amounts of sulfated and glucuronidated bile acids are excreted in urine. Information on the biliary excretion of these compounds is lacking. We used an intestinal perfusion method to determine the biliary excretion of sulfated and glucuronidated bile acids in eight patients with alcoholic cirrhosis and moderately severe cholestasis and compared results with urinary excretion rates. In bile, the patients excreted 508.7 μmoles per hr (mean) nonsulfated, nonglucuronidated bile acids, 8.1 μmoles per hr sulfated bile acids and 4.0 μmoles per hr glucuronidated bile acids. In urine, these patients excreted 0.27 μmoles per hr nonsulfated, nonglucuronidated bile acids, 0.88 μmoles per hr sulfated bile acids and 0.02 μmoles per hr glucuronidated bile acids. Sulfates and glucuronides of mono–, di– and trihydroxy bile acids were detected in urine and bile. In urine, tetrahydroxy bile acids were only excreted as nonsulfated and nonglucuronidated forms. The bile:urine excretion ratio of sulfated bile acids was 9:1 and of glucuronidated bile acids was 226:1. In alcoholic cirrhosis with cholestasis, biliary excretion is an important excretory route of sulfated and glucuronidated bile acids.
Acetaminophen–Induced Fulminant Hepatic Failure in Dogs
Authors: Ortega L. , Garcia Landa J.I. , Garcia Torres A. , Silecchia G. , Arenas J. , Suarez A. , Azcoitia Moreno M. , Esponera Sanz J. , Gonzalez Moreno E. , Cantero Balibrea J.L.
Published: March 2007

Results concerning morphological and biochemical changes following intravenous administration of different doses of acetaminophen in dogs are reported. Acetaminophen infusion, as a parenteral solution (500 mg per kg per 90 min), produced fulminant hepatitis characterized by a good correlation between Portmann's grade of lesion and percentage of necrosis. All animals died within 76 hr after intoxication. Analysis of biochemical parameters revealed positive correlation between serum bilirubin levels and severity of the hepatic lesion. The experimental model of acetaminophen–induced hepatotoxicity is proposed as a model for evaluation of the therapeutic efficacy of new medical and surgical procedures.
Transferrin Metabolism in Alcoholic Liver Disease
Authors: Potter Barry J. , Chapman Roger W.G. , Nunes Rosa M. , Sorrentino Dario , Sherlock Sheila
Published: March 2007

The metabolism of transferrin was studied using purified 125I–labeled transferrin in 11 alcoholic patients; six with fatty liver and five with cirrhosis. Six healthy subjects whose alcohol intake was les than 40 gm daily were studied as a control group.

There were no significant differences in the mean fractional catabolic rate and plasma volume in the alcoholic groups when compared with control subjects. A significantly decreased mean serum transferrin concentration was found in the alcoholic cirrhotic patients (1.8 ± 0.3 gm per liter vs. 2.9 ± 0.2; p < 0.01), resulting from diminished total body synthesis (0.9 ± 0.2 mg per kg per hr vs. 1.8 ± 0.2; p < 0.01). In contrast, in the patients with alcoholic fatty liver, the mean total body transferrin synthesis (2.4 ± 0.3 mg per kg per hr) was significantly increased when compared with controls (p < 0.05).

For all the alcoholic patients, the serum transferrin correlated with transferrin synthesis (r = +0.70; p < 0.01) but the serum iron did not.

These results suggest that, in alcoholic cirrhosis, transferrin synthesis is decreased, probably reflecting diminished synthetic capacity by the liver. In contrast, in patients with alcoholic fatty liver, transferrin turnover is accelerated.
Drug–Induced Hepatitis Associated With Anticytoplasmic Organelle Autoantibodies
Authors: Homberg Jean-Claude , Abuaf Nielsen , Helmy-Khalil Samir , Biour Michel , Poupon Raoul , Islam Shamsul , Darnis François , Levy Victor Georges , Opolon Pierre , Beaugrand Michel , Toulet Jacques , Danan Gaby , Benhamou Jean-Pierre
Published: March 2007

A study from five hepatology units documenting 157 cases of drug–induced hepatitis and a second study from a laboratory of immunology which tested more than 100,000 sera permitted us to establish the frequency of antiorganelle antibodies and their diagnostic value in drug–induced hepatitis. In drug–induced hepatitis caused by a heterogenous group of drugs consisting of ajmaline, aminopterine, isaxonine, isoniazid, perhexiline, phenylbutazone and troleandromycine, antiorganelle antibodies were absent or rare. In drug–induced hepatitis caused by another heterogenous group of drugs, including clometacin, fenofibrate, oxyphenisatin and papaverine, antismooth muscle, antinucleus and antimitochondria antibodies were found in isolation or in different combinations in 70% of cases. From the presence of antismooth muscle antibodies in sera, we could trace 30 cases of clometacin–induced hepatitis. The third group included drug–induced hepatitis with special antibody:iproniazid–induced hepatitis with antimitochondrial antibody 6 and tienilic acid (ticrynafen)–induced hepatitis with antiliver/kidney microsome antibody 2 (anti–LKM2). These two antibodies are rare in routine sera and were absent in patients who received the drug and had no liver damage. From the presence of corresponding antibodies, we detected six cases of iproniazid–induced hepatitis and 67 cases of tienilic acid–induced hepatitis. Antiorganelle antibodies found in high titers disappeared in 2 to 24 months following withdrawal of the offending drug. The fourth group was represented by halothane–induced hepatitis; antiliver/kidney microsome antibody 1 was weak and infrequent. Similarities between drug–induced hepatitis of the second group and lupoïd hepatitis suggest that drugs may reveal this spontaneous disorder. The specific antibody found in iproniazid and tienilic acid–induced hepatitis may suggest the site where the drug attaches in vivo. Immunoallergic hypersensitivity seems to be the mechanism involved in halothane–induced hepatitis; autoimmune phenomenon may play a role in liver damage caused by tienilic acid.
Function of the Autonomic Nervous System in Patients With Hepatic Encephalopathy
Authors: Lenz Kurt , Hörtnagl Heide , Magometschnigg Dieter , Kleinberger Gunter , Druml Wilfred , Laggner Anton
Published: March 2007

To obtain further pathophysiological details concerning the development of cardiovascular disturbances in severe liver disease, the state of the autonomic nervous system, the function of the baroreceptor reflex pathway and the responsiveness of the cardiovascular system to noradrenaline, angiotensin II and isoprenaline were investigated in 11 patients with hepatic encephalopathy and in 10 healthy control subjects. Increased plasma levels of noradrenaline and adrenaline and an attenuated increase in heart rate in response to atropine were found in patients with hepatic encephalopathy. These changes and the hemodynamic disturbances tended to be more pronounced in patients with hepatic encephalopathy Grades III-IV as compared to hepatic encephalopathy Grades I-II.

The increase in systolic blood pressure induced by infusion of noradrenaline (400 ng per kg per min) and angiotensin II (20 ng per kg per min) was higher in the patients than in healthy control subjects (hepatic encephalopathy Grades I-II: p < 0.001; hepatic encephalopathy Grades III-IV: p < 0.02). The changes in mean and diastolic blood pressure in response to angiotensin II were more pronounced in hepatic encephalopathy grades I-II than in hepatic encephalopathy Grades III-IV (p < 0.02). The decrease of heart rate in response to blood pressure increase in patients with hepatic encephalopathy was not different from control subjects except a smaller decrease during angiotensin II infusion in hepatic encephalopathy grades III-IV (p < 0.05). The responsiveness to isoprenaline was diminished (p < 0.001).

The present results indicate that the increased activity of the sympathetic nervous system in hepatic encephalopathy is associated with decreased parasympathetic tone. In addition, patients with hepatic encephalopathy have normal function of the baroreceptor reflex and excellent responsiveness of vascular tissue to endogenous vasoconstrictors.
Hepatitis B Vaccine: Low Postvaccination Immunity in Hospital Personnel Given Gluteal Injections
Authors: Lindsay Karen L. , Herbert David A. , Gitnick Gary L.
Published: March 2007

Although other investigators have found excellent response rates to the hepatitis B vaccine, we report here an unusually low rate of seroconversion following hepatitis B vaccination in a group of apparently healthy medical center personnel. Only 67% of these individuals developed adequate postvaccination antibodies to HBsAg, in contrast to 85 to 96% in other studies. A significant decrease in seroconversion with increasing age was noted with a 54% seroconversion rate in vaccines over the age of 40, all of whom had received gluteal injections. Employees at another facility had been given deltoid injections from the same vaccine lot and had an overall seroconversion rate of 90%. Subsequently, nonresponders from the first group were revaccinated. Seven of the ten individuals tested developed anti–HBs. We believe the relatively low rate of seroconversion in individuals above the age of 40 may have been related to gluteal injection of the hepatitis B vaccine, and further investigation is warranted.
Establishment of A Cell Line From A Woodchuck Hepatocellular Carcinoma
Authors: Unoura Masashi , Kobayashi Kenichi , Fukuoka Kenichi , Matsushita Fumiaki , Morimoto Hideo , Oshima Tohru , Kaneko Shuichi , Hattori Nobu , Murakami Seishi , Yoshikawa Hiroshi
Published: March 2007

A new cell line derived from a woodchuck hepatocellular carcinoma serially transplanted in athymic nude mice has been established and named WH257GE10. The original tumor in the nude mouse system produces woodchuck hepatitis surface antigen and albumin. In addition, woodchuck hepatitis virus DNA is integrated into cellular DNA. Adaptation of the cells to the in vitro culture condition was completed after 15 months with the doubling time of 40 hr. The morphologic features of the cell by light microscopy are of an epithelial type. The modal chromosome number is 36 and the karyotype is mainly metacentric, similar to that observed in normal woodchuck liver cells. Ornithine and tyrosine aminotransferase activities were detected. Production of albumin was demonstrated in the cytoplasm by indirect immunofluorescence. Integration of woodchuck hepatitis virus DNA was shown by Southern blot analysis, although the secretion of woodchuck hepatitis surface antigen was not detected. This cell line provides an excellent in vitro model to study human hepatocellular carcinoma related to hepatitis B virus.
A Randomized Study of the Effects of Adenine Arabinoside 5′–Monophosphate (Short or Long Courses) and Lymphoblastoid Interferon on Hepatitis B Virus Replication
Authors: Lok Anna S.F. , Novick David M. , Karayiannis Peter , Dunk Arthur A. , Sherlock Sheila , Thomas Howard C.
Published: March 2007

A previous randomized controlled study has shown a 30% rate of HBe antigen/antibody serocon–version within 1 year of a month course of adenine arabinoside–5′–monophosphate; no seroconversion occurred in the control group. In this study of patients derived from the same population, 45 hepatitis B virus carriers with chronic liver disease were randomized to receive either a short (4–week) course of adenine arabinoside–5′–monophosphate, a long (7 to 8–week) course of adenine arabinoside–5′–monophosphate or a 12–week course of lymphoblastoid interferon. Long–lasting suppression of hepatitis B virus replication with disappearance of serum hepatitis B virus DNA and clearance of HBeAg occurred within 12 months of treatment in four patients who received the short course of adenine arabinoside–5′–monophosphate and in five who received interferon. Of the nine responders, four also lost HBsAg. A response to antiviral therapy was accompanied by clinical and biochemical evidence of improvement in liver disease. None of the patients who received a long course of adenine arabinoside–5′–monophosphate responded. Peripheral neuropathy and myalgia were the most serious adverse effect affecting three recipients of the short course of adenine arabinoside–5′–monophosphate and eight recipients of the long course. Thrice weekly administration of interferon was well–tolerated. Further studies to identify the characteristics of the “responder patients” and large–scale controlled trials of antiviral therapy in these subgroups are indicated.
Biochemical Indicators of Vitamin A Depletion in Children With Cholestasis
Authors: Amédée-Manesme Olivier , Furr Harold C. , Alvarez Fernando , Hadchouel Michelle , Alagille Daniel , Olson James Allen
Published: March 2007

Biochemical indicators of vitamin A status were measured in 24 children (1 month to 6 years old) with severe cholestasis starting early in life and in 21 children (3 months to 13 years old) with liver disease but without cholestasis. Liver vitamin A concentrations, expressed as micrograms of retinol per gram of liver (mean ± S.D.), were 6.3 ± 7.1 (range: 0.14 to 28) and 143 ± 108 (range: 18 to 424), respectively, in cholestatic and noncholestatic children. In infants < 6 months of age, liver vitamin A values < 10 μg per gm were found in 14 of 17 cholestatic children but in none of 3 noncholestatic subjects. Plasma vitamin A values, expressed as micrograms of retinol per deciliter (mean ± S.D.), were 23 ± 18 (range: 3 to 62) and 46 ± 33 (range: 14 to 125), respectively, for the two groups. Plasma retinol values < 10 μg per dl were always associated with liver concentrations < 10 μg per gm. Plasma retinol–binding protein was only reduced to 71% of control values in cholestatic children. The fatty acid composition of liver retinyl esters was unaffected by any condition studied. Infants with chronic cholestasis are in a precarious nutritional status very early in life relative to liver reserves of vitamin A. Plasma vitamin A values, unless < 10 μg retinol per dl, are poor indicators of inadequate vitamin A status.
Reticuloendothelial System Fc Receptor–Mediated Clearance of Igg–Tagged Erythrocytes From the Circulation of Patients With Idiopathic Ulcerative Colitis and Chronic Liver Disease
Authors: Minuk Gerald Y. , Hershfield Noel B. , Lee Weng Y. , Maccannell Keith L. , Preshaw Roy , Price Lorne M. , Shaffer Eldon A. , Sutherland Lloyd R.
Published: March 2007

Immune complexes may be important in the pathogenesis of the liver disease associated with idiopathic ulcerative colitis. In the present study, we documented Fc receptor–mediated clearance by the reticuloendothelial system of immune complex–like material from the systemic circulation of 25 healthy control subjects, 19 patients with ulcerative colitis alone, 9 patients with ulcerative colitis and elevated liver enzyme tests and 8 patients with various other formsof chronic liver disease. Following an intravenous infusion of IgG–tagged 51Cr–labeled autologous erythrocytes, serial blood samples were drawn over a 2–hr period of time, and computer–generated clearance curves were obtained. The time required for clearance of 50% of infused erythrocytes (T1/2) was then calculated. Serum immunoglobulin (IgA, IgG and IgM), complement (C3 and C4) and immune complex–like activity (IgG and IgM types) were also determined. Sixteen of 19 (84%) ulcerative colitis patients and 7 of 8 (88%) chronic liver disease patients had normal clearance T1/2's (when compared to 25 healthy controls). Conversely, only 1 of 9 (11%) ulcerative colitis + chronic liver disease patients demonstrated normal clearance function. Aside from serum IgM levels, the results of serum immunoglobulin, complement and immune complex–like determinations were similar in ulcerative colitis and ulcerative colitis + chronic liver disease patients. Serum IgM levels, however, were significantly decreased in ulcerative colitis patients and increased in ulcerative colitis + chronic liver disease patients (p < 0.001).

These results indicate that the reticuloendothelial system of patients with ulcerative colitis and chronic liver disease is impaired in its ability to clear immune complex–like material from the systemic circulation. This finding tendsto support the hypothesis that immune complexes are of pathogenic importance in the liver disease associated with idiopathic ulcerative colitis.