bluuebunny/crossref_metadata_2025 huggingface dataset:
Forebrain connectivity of the prefrontal cortex in the marmoset monkey (Callithrix jacchus): An anterograde and retrograde tract‐tracing study
Authors: Roberts Angela C. , Tomic Davorka L. , Parkinson Caroline H. , Roeling Tom A. , Cutter David J. , Robbins Trevor W. , Everitt Barry J.
Published: March 2007

The cortical and subcortical forebrain connections of the marmoset prefrontal cortex (PFC) were examined by injecting the retrograde tracer, choleratoxin, and the anterograde tracer, biotin dextran amine, into four sites within the PFC. Two of the sites, the lateral and orbital regions, had previously been shown to provide functionally dissociable contributions to distinct forms of behavioral flexibility, attentional set‐shifting and discrimination reversal learning, respectively. The dysgranular and agranular regions lying on the orbital and medial surfaces of the frontal lobes were most closely connected with limbic structures including cingulate cortex, amygdala, parahippocampal cortex, subiculum, hippocampus, hypothalamus, medial caudate nucleus, and nucleus accumbens as well as the magnocellular division of the mediodorsal nucleus of the thalamus and midline thalamic nuclei, consistent with findings in the rhesus monkey. In contrast, the granular region on the dorsal surface closely resembled area 8Ad in macaques and had connections restricted to posterior parietal cortex primarily associated with visuospatial functions. However, it also had connections with limbic cortex, including retrosplenial and caudal cingulate cortex as well as auditory processing regions in the superior temporal cortex. The granular region on the lateral convexity had the most extensive connections. Based on its architectonics and functionality, it resembled areas 12/45 in macaques. It had connections with high‐order visual processing regions in the inferotemporal cortex and posterior parietal cortex, higher‐order auditory and polymodal processing regions in the superior temporal cortex. In addition it had extensive connections with limbic regions including the amygdala, parahippocampal cortex, cingulate, and retrosplenial cortex. J. Comp. Neurol. 502:86–112, 2007. © 2007 Wiley‐Liss, Inc.
γ‐Aminobutyric acid‐containing sympathetic preganglionic neurons in rat thoracic spinal cord send their axons to the superior cervical ganglion
Authors: Ito Tetsufumi , Hioki Hiroyuki , Nakamura Kouichi , Tanaka Yasuyo , Nakade Hiroyuki , Kaneko Takeshi , Iino Satoshi , Nojyo Yoshiaki
Published: March 2007

γ‐Aminobutyric acid (GABA)‐containing fibers have been observed in the rat superior cervical ganglion (SCG) and, to a lesser extent, in the stellate ganglion (STG). The aim of present study is to clarify the source of these fibers. No cell body showed mRNAs for glutamic acid decarboxylases (GADs) or immunoreactivity for GAD of 67 kDa (GAD67) in the cervical sympathetic chain. Thus, GABA‐containing fibers in the ganglia are suggested to be of extraganglionic origin. GAD67‐immunoreactive fibers were found not in the dorsal roots or ganglia, but in the ventral roots, so GABA‐containing fibers in the sympathetic ganglia were considered to originate from the spinal cord. Furthermore, almost all GAD67‐immunoreactive fibers in the sympathetic ganglia showed immunoreactivity for vesicular acetylcholine transporter, suggesting that GABA was utilized by some cholinergic preganglionic neurons. This was confirmed by the following results. 1) After injection of Sindbis/palGFP virus into the intermediolateral nucleus, some anterogradely labeled fibers in the SCG were immunopositive for GAD67. 2) After injection of fluorogold into the SCG, some retrogradely labeled neurons in the thoracic spinal cord were positive for GAD67 mRNA. 3) When the ventral roots of the eighth cervical to the fourth thoracic segments were cut, almost all GAD67‐ and GABA‐immunoreactive fibers disappeared from the ipsilateral SCG and STG, suggesting that the vast majority of GABA‐containing fibers in those ganglia were of spinal origin. Thus, the present findings strongly indicate that some sympathetic preganglionic neurons are not only cholinergic but also GABAegic. J. Comp. Neurol. 502:113–125, 2007. © 2007 Wiley‐Liss, Inc.
Proline trapping in granulomas, the site of collagen biosynthesis in murine schistosomiasis
Authors: Dunn Michael A. , Seifter Sam , Hait Penelope K.
Published: March 2007

Proline, a critical substrate for collagen synthesis, is increased in liver undergoing fibrosis. In mice with schistosomiasis, the incorporation of proline into collagen occurs within liver granulomas. To study the interaction of liver cells and granulomas in the development of fibrosis, we assayed the enzymes that catalyze the formation and degradation of proline in isolated granulomas and liver.

Two sequential enzymes involved in the formation of proline from arginine are ornithine-δ-aminotransferase and Δ1-pyrroline-5-carboxylate (P5C) reductase. Activities of both these enzymes in granulomas were approximately 10% of those in liver, expressed on the basis of DNA content.

The enzymes involved in degradation of proline are proline oxidase and P5C dehydrogenase; both are present in liver cells. In isolated granulomas, activity of proline oxidase was minimal, and P5C dehydrogenase activity was absent. These findings suggest that the metabolism of proline within granulomas differs greatly from that in liver cells. Earlier studies showed that exogenous proline enters granulomas and is rapidly incorporated into collagen. The combined findings raise the possibility that granulomas serve as a proline trap. Proline can enter this compartment and can be incorporated into collagen; however, proline within granulomas cannot readily be diverted into other pathways by degradation.
Hepatitis B viral markers in severe viral hepatitis: Influence of steroid therapy
Authors: Greenberg Harry B. , Robinson William S. , Knauer Michael C. , Gregory Peter B.
Published: March 2007

In our double-blind randomized trial of methylprednisolone vs. placebo in severe viral hepatitis, 16 patients with hepatitis B (8 on steroid, 8 on placebo) were followed for at least 4 weeks. Four of the eight patients receiving methylprednisolone eventually died and all patients on placebo survived. Despite marked reduction in serum IgG in steroid-treated patients, the decline in HBsAg titer and disappearance of Dane particle markers was the same in both treatment groups. A nonspecific depression of anti-HBc was noted in patients given steroid. There is no evidence that corticosteroid therapy accelerates viral replication when the acute hepatitis is severe.
Modification of galactosamine-induced liver injury in rats by reticuloendothelial system stimulation or depression
Authors: Al-Tuwaijri Ali , Akdamar Kemal , di Luzio Nicholas R.
Published: March 2007

The reticuloendothelial system has been implicated in galactosamine-induced liver injury because of a correlation between phagocytic alterations induced by colloidal carbon or endotoxin, and development of liver necrosis. To evaluate this concept, the influence of galactosamine on liver function and histology was determined in rats in which the reticuloendothelial system was normal, stimulated, or depressed. Methyl palmitate was used as a reticuloendothelial system suppressant, and glucan was used as a reticuloendothelial system activating agent. Administration of galactosamine to control rats resulted in hypoglycemia and increased serum bilirubin concentration, elevated serum glutamic oxalacetic transaminase, lactic dehydrogenase and glutamic pyruvic transaminase activities, and retention of sodium sulfobromophthalein. Histological studies revealed hepatic necrosis, and a polymorphonuclear and lymphocytic cellular infiltrate in galactosamine-treated rats. Pretreatment of rats with methyl palmitate inhibited galactosamine-induced alterations in serum glucose concentration, glutamic oxalacetic transaminase and lactic dehydrogenase activities, and sodium sulfobromophthalein retention. Liver necrosis and inflammatory reactions were also reduced in methyl palmitate-treated galactosamine-injected animals. In contrast, activation of the reticuloendothelial system by glucan increased galactosamine-induced alterations in serum bilirubin, glucose and cholesterol concentrations, glutamic oxalacetic transaminase, glutamic pyruvic transaminase and lactic dehydrogenase activities, and sodium sulfobromophthalein retention. Liver necrosis and inflammation were also increased. These findings suggest that the degree of galactosamine-induced liver injury is directly correlated with macrophage function when specific macrophage-modifying agents are used.
In vitro effect of bile salts on rat liver plasma membrane, lipid fluidity, and ATPase activity
Authors: Scharschmidt Bruce F. , Keeffe Emmet B. , Vessey Donald A. , Blankenship Nancy M. , Ockner Robert K.
Published: March 2007

Considerable evidence suggests that liver plasma membrane (LPM) NaK-ATPase [(Na+ + K+)-dependent adenosinetriphosphatase] and Mg-ATPase (Mg2+-dependent adenosinetriphosphatase) activity and lipid fluidity are important in liver cell functions such as bile formation. However, little is known regarding factors which might alter these membrane properties in vivo. Bile salts are actively concentrated by liver cells under normal conditions and reach even higher tissue concentrations in cholestasis. Since current methodology does not permit investigation of the effect of bile salts on LPM in vivo, we have examined the effects of bile salts in vitro on isolated rat LPM essentially free of organelle contamination and enriched 52.9-, 23.8-, and 27.8-fold in NaK-ATPase, 5′-nucleotidase, and alkaline phosphatase, respectively, compared with homogenate. We found that taurocholate (0.5 to 4.0 mM), taurochenodeoxycholate (0.25 to 4.0 mM), deoxycholate (0.25 to 4.0 mM), but not dehydrocholate (0.25 to 4.0 mM) caused immediate, concentration-dependent inhibition of LPM Mg- and NaK-ATPase which at low bile salt concentration (1.0 mM) was reversible. By contrast, taurocholate (1 to 4 mM) had no effect on LPM 5′-nucleotidase activity. Both 1 mM taurocholate and taurochenodeoxycholate caused a decrease in the apparent Km for ATP of NaK-ATPase, but not of Mg-ATPase, and 1 mM taurochenodeoxycholate caused no significant change in the activation of either Mg- or NaK-ATPase by cations. Finally, LPM lipid fluidity measured by fluorescence polarization using 1,6-diphenyl-1,3,5-hexatriene as a probe was reversibly increased by taurocholate, taurochenodeoxycholate, and deoxycholate, but not dehydrocholate; the effect of taurochenodeoxycholate on lipid fluidity was confirmed by electron spin resonance using 5-(2,2-dimethyl-N-oxyl-oxayalidine)-stearic acid as a probe. However, by both techniques, the effect of low concentrations of these bile salts on ATPase activity was independent of detectable changes in fluidity.

These findings indicate that at concentrations comparable to those reported for liver tissue endogenous, micelle-forming bile salts reversibly inhibit LPM ATPases and reversibly increase LPM lipid fluidity in vitro; these two effects being dissociable at low bile salt concentrations. It is possible that bile salts may have similar effects in vivo, particularly under cholestatic conditions.
Prognostic indicators of hepatic injury following jejunoileal bypass performed for refractory obesity: A prospective study
Authors: Haines Norman W. , Baker Alfred L. , Boyer James L. , Glagov Seymour , Schneir Harvey , Jaspan Jonathan , Ferguson Donald J.
Published: March 2007

To evaluate factors predisposing to liver injury following jejunoileal bypass, 27 patients underwent clinical evaluation and liver biopsy prior to bypass and at 3, 6, 12, 18, and 24 months and yearly thereafter. Nineteen patients developed increased fatty infiltration of the liver, 1 developed cryptogenic cirrhosis, and 7 developed steatonecrosis, central hyaline sclerosis, or cirrhosis indistinguishable from alcoholic liver disease during the period of rapid weight loss. Two of these 7 patients developed clinical liver failure; inactive cirrhosis evolved after parenteral alimentation and reanastomosis in one, and after oral nutritional supplementation in the other. Four of 5 asymptomatic patients resolved to inactive cirrhosis as weight loss diminished. Each of the 7 patients had pericentral fibrosis on pre-bypass liver biopsies, suggesting a previous hepatic injury. These patients were older (p < 0.02) and, 3 months following bypass, had greater cumulative per cent weight loss (p < 0.05), higher levels of serum aspartate aminotransferase (p < 0.005), and greater 45-min bromosulfophthalein retention (p < 0.02). Histologic evidence of pericentral fibrosis identified patients at risk to develop steatonecrosis and cirrhosis; these lesions occurred in older patients who had greater weight loss following jejunoileal bypass.
Structural heterogeneity of hepatocyte “tight” junctions: A quantitative analysis
Authors: Lagarde Suzanne , Elias Elwyn , Wade James B. , Boyer James L.
Published: March 2007

Freeze fracture analyses of hepatocyte tight junctions reveal interconnecting strands which represent a semipermeable blood-bile barrier. In epithelia, strand number can be correlated with transepithelial resistance and junctional permeability, but a functional relationship is not always seen. We have devised an analytical method to measure accurately strand number as well as junction depth over a large area of junction. Measurements were obtained in five bile fistula rats and two marine elasmobranchs (little skates). In addition, choleretic infusions of 120 μmoles of taurodehydrocholate were administered to four additional rats over 1 hr to determine if functional changes in ion and fluid movement are associated with alternations in junctional structure. Using a microcomputer with a sonic digitizer, strand number and junction depth were obtained at intervals of 0.1 to 0.2 μ from transmission electron micrographs of fractures of rat and skate liver. Strand number averaged 4.1 ± 1.1 in control rats (798 measurements) and 4.1 ± 1.3 in the taurodehydrocholate-stimulated animals (296 measurements). Junction depths averaged 0.148 ± 0.092 μm in controls and increased to 0.167 ± 0.121 μm in taurodehydrocholate-stimulated rats, a difference which reached significance at the p < 0.06 level. Similarly, values were obtained in skate livers where central zone pigment granules facilitated dissection of portal and central portions of lobule. Central zone strand number and junction depth averaged 5.1 ± 1.6 and 0.178 ± 0.100 μm, respectively (439 measurements), and were indistinguishable from values obtained from portal regions −5.0 ± 1.9 and 0.182 ± 0.099 μm, respectively (217 measurements). Although no quantitative differences in junction structure was observed in these studies, considerable variation was noted in junction depth (0.013 to 0.670 μm in the rat and 0.008 to 0.600 μm in skates) and number. We conclude that the anatomical barrier which forms the normal hepatocyte tight junction is a highly varied structure. If junctional structure as revealed by freeze fracture analysis correlates with changes in permeability, then permeability should vary considerably at multiple points along the surface of individual hepatocytes and would not be detected by present quantitative approaches which average junctional strand number and depth. Alternatively, regulation of junctional permeability may be more dependent on structural elements which are beyond the resolution provided by freeze fracture technique.
Granuloma collagenase and EDTA-sensitive neutral protease production in hepatic murine schistosomiasis
Authors: Takahashi Shizuko , Simpser Edwin
Published: March 2007

Mice infected with Schistosoma mansoni represent a model for study of hepatic fibrosis in humans. Production of trypsin-activatable inactive collagenase and EDTA-sensitive neutral protease was measured in the culture medium in which granuloma explants or primary cultures were maintained. Collagenase production was maximal in granulomas obtained from liver of mice 8 weeks postinfection and was inhibited by Actinomycin D or cycloheximide, and enhanced by lymphocyte factor(s) or heparin. Isolated schistosome eggs did not release these enzymatic activities but did release EDTA-insensitive protease activity. Both enzymes were separated by ion-exchange chromatography and purified to homogeneity. Isolated collagenase had an isoelectric point of 6.2 and molecular weight of 60,000 and had the functional characteristics of a tissue collagenase. The specific activity of collagenase was 33 units per mg protein at an optimum pH 7.5 and lacked proteolytic activity against noncollagenous protein substrates. Isolated EDTA-sensitive neutral protease had specific caseinolytic activity of 150 units per mg protein and gelatinolytic activity of 300 units per mg protein at an optimun pH 7.5; the enzyme lacked activity against undenatured collagen. Isoelectric point was pH 6.0. Protease activity was inhibited by known inhibitors of collagenases. Production and activation of EDTA-sensitive neutral protease and collagenase accompany increased collagen synthesis and content in the liver of mice 8 weeks postinfection with S. mansoni cercariae. Continued accumulation of liver collagen under these conditions suggests an insufficiency in collagenase activity relative to the increase in collagen synthesis.
Muscle protein breakdown in liver cirrhosis and the role of altered carbohydrate metabolism
Authors: Marchesini Giulio , Zoli Marco , Angiolini Angela , Dondi Cristina , Bianchi Francesco B. , Pisi Emilio
Published: March 2007

The rates of muscle protein breakdown, as estimated by the urinary excretion of 3-methylhistidine, were assessed in 30 cirrhotics and 15 controls on a strictly controlled diet. 3-Methylhistidine excretion was increased in cirrhotics irrespective of the etiology of the disease, and correlated with basal glucagon levels and with the insulin/glucagon ratio. In nine cirrhotics and nine age- and sexmatched controls, similar correlations were found between 3-methylhistidine and the areas under 24-hr glucagon or insulin/glucagon curves. A larger amount of 3-methylhistidine was excreted during the nighttime than during the daytime, when glucagon secretion was suppressed and the insulin/glucagon ratio was increased. It is concluded that muscle protein catabolism is increased in cirrhotics, possibly as a result of hyperglucagonemia or the reduced insulin/glucagon ratio. These data agree with the clinical observation of a progressive reduction in lean body mass which becomes evident in an advanced stage of the disease.
The presence of a microsomal UDP-glucuronyl transferase for bilirubin in homozygous jaundiced gunn rats and in the crigler-najjar syndrome
Authors: Odell Gerard B. , Cukier Julio O. , Gourley Glenn R.
Published: March 2007

The infusion of a closely related derivative of bilirubin, its dimethyl diester (DME), into jaundiced (jj) Gunn rats was associated with biliary excretion of mono-and diglucuronides of bilirubin. In vitro incubation of DME with liver microsomes from jj rats demonstrated sequential demethylation and glucuronidation of DME. Liver microsomes from a patient with the Crigler-Najjar syndrome were unable to form glucuronides of bilirubin in vitro unless DME was used as substrate. The results suggest that the deficiency in Gunn rats and in the Crigler-Najjar syndrome may be due to a structural defect in the microsomal matrix which contains glucuronyl transferase. This interpretation envisions a microenvironment of the transferase enzyme which is either impermeable to bilirubin or induces conformational changes which interfere with glucuronidation.
Hepatitis B virus DNA in the sera of HBsAg carriers: A marker of active hepatitis B virus replication in the liver
Authors: Bonino Ferruccio , Hoyer Bill , Nelson Judith , Engle Ronald , Verme Giorgio , Gerin John
Published: March 2007

Sera and liver biopsies from 30 Italian patients, carriers of HBsAg for at least 3 years, were examined for markers of hepatitis B virus (HBV) infection by serological assays and immunofluorescence. Biopsies were analyzed for HBcAg, HBsAg, and δ antigen by immunofluorescence; sera were assayed for HBsAg/anti-HBs, HBcAg/anti-HBc, HBeAg/anti-HBe, δ/anti-δ, HBV-specific DNA polymerase activity and the presence of HBV DNA. HBcAg, HBeAg, and DNA polymerase tests were positive in the sera of 71, 86, and 57%, respectively, of carriers with intrahepatic HBcAg. HBV DNA was detected in 100% of patients expressing HBcAg in the liver with a strong correlation between the concentration of serum DNA and the intensity of HBcAg immunofluorescence in the liver. HBV DNA was detected in the sera of 63% of carriers with intrahepatic δ where the other markers of HBV replication (HBeAg, DNA polymerase) were undetectable. The assay for serum HBV DNA appears to be an excellent noninvasive method for detecting active replication of HBV in HBsAg carriers.
Membrane traffic at the hepatocyte’s sinusoidal and canalicular surface domains
Authors: Evans Howard W.
Published: March 2007

Traffic in the environs of regions of the hepatocyte’s plasma membrane is heavy. A fuller understanding of the nature and control of this membrane traffic depends on the appreciation of the hepatocyte’s plasma membrane. This conglomerate consists of a receptor-rich and metabolically dynamic blood-sinusoidal domain which is separated from the bile canalicular domain by a lateral domain which participates in cell-cell interactions (1, 2). The rapid receptor-mediated endocytotic uptake and processing of membrane receptor-ligand complexes occurring against a background of hepatic secretion is a key step in understanding relationships between intracellular membrane compartments and the maintenance of differentiated plasma membrane domains. The fate of a wide range of interiorized ligands appears to be decided upon transfer to a Golgi-endoplasmic reticulum lysosomal (GERL) locus where a processing decision is made leading to release of ligands in an intact form into sinusoids or bile canaliculi, or to degradation. This review discusses properties of receptor-binding sites for hormones and metabolites which are located primarily at the sinusoidal plasma membrane, the biogenesis of this membrane, and the various traffic routes of membrane-ligand complexes traversing the hepatocyte interior.
Experimental HBV and δ infections of chimpanzees: Occurrence and significance of intrahepatic immune complexes of HBcAg and δ antigen
Authors: Rizzetto Mario , Canese Maria G. , Purcell Robert H. , London William T. , Sly David L. , Gerin John L.
Published: March 2007

The occurrence and pathogenetic role of intrahepatic deposits of immunoglobulins in experimental viral infection have been evaluated by determining with immunofluorescence their capacity to fix complement in vitro [in vitro complement fixation (VCF)]. Liver biopsies from chimpanzees chronically or acutely infected with hepatitis B virus or the hepatitis B surface antigen (HBsAg)-associated δ agent were used in the study. VCF was observed in each animal expressing hepatitis B core antigen (HBcAg) or δ antigen in the liver and concurrently circulating the homologous antibody in the blood. In acutely infected animals, VCF appeared at the same time that the homologous serum antibody appeared, and the intensity of VCF staining was proportional to the antibody titer in the serum. In animals expressing sequentially the HBcAg/antibody system and then δ antigen and antibody to δ, VCF was first observed in HBcAg-containing nuclei and then in nuclei expressing δ antigen. There was no relationship between VCF and intrahepatic expression of HBsAg or serologic expression of hepatitis B e antigen (HBeAg).

A positive VCF reaction appears related to the formation of intrahepatic immune complexes between HBcAg or δ antigen and the homologous antibody. Although acute hepatitis developed in parallel with the occurrence of VCF in two animals, strong VCF fluorescence was also observed in each of the asymptomatic carriers of HBsAg, and, in one of them, preexisting VCF staining of HBcAg disappeared in parallel with development of acute hepatitis.

In experimentally infected chimpanzees, the finding in liver biopsies of immune complexes detectable by VCF appears to be a common epiphenomenon without pathogenic significance.
Chronic non-A, non-B hepatitis: Ultrastructural and serologic studies
Authors: Marciano-Cabral Francine , Rublee Karen L. , Carithers Robert L. , Galen Edward A. , Sobieski Thomas J. , Cabral Guy A.
Published: March 2007

Liver biopsies from five patients with chronic non-A, non-B (NANB) hepatitis were examined by electron microscopy for hepatocellular alterations. Circular fused membranes were observed within the cytoplasm of hepatocytes of four of the patients. Aggregates of intranuclear particles, measuring 22 ± 2 nm in diameter, were also seen in two of the biopsies in which fused membranes were identified. Sera of all five patients formed precipitin lines detectable by counterimmunoelectrophoresis when reacted with serum from an individual convalescent from posttransfusion NANB hepatitis. Using this convalescent serum as an antibody source, complexes of 22 ± 2 nm particles were identified in three of the chronic patient sera by immunoelectron microscopy. These observations suggest that at least one of the agents responsible for NANB hepatitis elicits both nuclear and cytoplasmic modifications. Furthermore, the 22 ± 2 nm particles circulating in the sera of the chronic NANB patients may represent components related to NANB hepatitis agent.
Delayed HBsAg clearance in chronic hepatitis B viral infection
Authors: Lindsay Karen L. , Redeker Allan G. , Ashcavai Mary
Published: March 2007

Seven patients are described in whom HBsAg persisted for 13 to 98 months after acute viral hepatitis B and then became nondetectable. All patients subsequently developed anti-HBs. During the period of HBs-antigenemia, liver biopsies in five patients showed persistent viral hepatitis. Retrospectively, impending negativity of HBsAg was predictable in five patients by a decrease in HBsAg titer, and in four patients by persistent normalization of serum alanine aminotransferase. Although delayed clearance of HBsAg in patients with chronic hepatitis B virus infection is uncommon, it appears to be predictable.
Effect of ethanol on the synthesis and secretion of hepatic secretory glycoproteins and albumin
Authors: Tuma Dean J. , Jennett Richard B. , Sorrell Michael F.
Published: March 2007

The effects of ethanol on the synthesis and secretion of serum glycoproteins and albumin, a nonglycosylated protein, were studied in rat liver slices. Serum glycoproteins and albumin were determined by immunoprecipitation from either the incubation medium or from the washed slices. When ethanol (10 mM) was present in the incubation medium, [14C]glucosamine incorporation in secretory glycoproteins was decreased. This inhibitory effect was, however, much greater in the secretory proteins released into the medium than in those retained in the liver slices. Similar inhibitions by ethanol were also observed when leucine or valine were used as a label for either total export proteins or albumin. Since ethanol impaired protein synthesis, an inhibitor of protein synthesis, cycloheximide, was used so that both the control and ethanol-treated slices had identical pools of protein acceptors available for glycosylation. When cycloheximide alone was added to the slices, glucosamine radioactivity of secretory glycoproteins was equally reduced in both the medium and the liver. When cycloheximide and ethanol were both present, decreased appearance of glucosamine-labeled proteins in the medium was observed when compared to the slices containing cycloheximide alone; however, radioactivity of secretory glycoproteins retained in the liver was elevated. Ethanol also decreased the appearance of fucose-labeled glycoproteins in the medium without altering fucose incorporation into the total pool of secretory glycoproteins. The effects of ethanol on hepatic protein secretion independent of its effect on synthesis were further determined by prelabeling proteins with either [14C]leucine or [14C]fucose. Ethanol impaired the secretion of these prelabeled proteins into the medium. The results of this study show that ethanol impairs both the synthesis and secretion of secretory glycoproteins and albumin.
Effect of fasting on organic anion uptake by isolated rat liver cells
Authors: Laperche Yannick , Preaux Anne-Marie , Feldmann Gerard , Mahu Jean-Louis , Berthelot Pierre
Published: March 2007

In order to determine if the delayed clearance of organic anions observed in vivo after fasting can be related to an alteration of cell membrane carriers, kinetics of sulfobromophthalein (BSP) uptake were determined in isolated rat liver cells obtained from 48-hr starved rats. Surprisingly, in fasted rats the existence of two carriers can be directly revealed by classical kinetic plots. The high-affinity component, inhibited by Na+-taurocholate, has a Km of 0.5 ± 0.2 μM and a Vmax of 0.2 ± 0.1 nmole per min per 106 cells; the low-affinity component, which is not sensitive to Na+-taurocholate, has a Km of 21.2 ± 3.2 μM and a Vmax of 4.8 ± 0.9 nmoles per min per 106 cells. Comparison with control cells shows that fasting does not modify the total capacity of the liver cell membrane carriers to take up BSP. However, alterations in the kinetic parameters of the two uptake components were observed: a 53% decrease in the affinity of the low-affinity component and a 50% reduction in the capacity of the high-affinity uptake. These alterations, together with the observed decrease in hepatic blood flow and/or the increase in BSP efflux from the hepatocytes, could be involved in the delayed clearance of BSP and other anionic compounds occurring in vivo after fasting.
Morphologic features of chronic hepatitis associated with primary sclerosing cholangitis and chronic ulcerative colitis
Authors: Ludwig Jurgen , Barham Steven S. , Larusso Nicholas F. , Elveback Lila R. , Wiesner Russell H. , McCall John T.
Published: March 2007

Histologic, ultrastructural, chemical, and statistical methods were used to study liver biopsy and autopsy specimens from 43 patients who had primary sclerosing cholangitis (PSC), with or without chronic ulcerative colitis (CUC), and from 19 patients who had CUC without PSC. In all study groups, essentially the same abnormalities were found in the hepatic parenchyma outside the major bile ducts, although nondiagnostic tissue samples were observed also. Specimens from patients with extrahepatic PSC were indistinguishable from those from patients with combined extra- and intrahepatic PSC. Common findings included periductal fibrosis and inflammation, portal edema and fibrosis, focal proliferation of bile ducts and ductules, focal bile duct obliteration and loss of bile ducts, copper deposition, and cholestasis. Proliferation of bile ducts in some portal tracts and obliteration or absence of bile duct in others were the most characteristic changes. In most specimens, inflammatory changes appeared mild, yet biliary cirrhosis had developed in 34% of the patients. Specimens from patients with PSC, with or without CUC, more often contained bile and strikingly increased stainable copper (Grades 2 and 3) than did specimens from patients with CUC without PSC. Hepatic copper contents, measured by atomic absorption spectrophotometry, also were higher in specimens from patients with PSC. Study of PCS specimens by transmission electron microscopy and by energy-dispersive X-ray microanalysis revealed that most copper was sequestered in lipolysosomes. The recognition of strikingly similar morphologic features in many liver specimens from patients with either PSC or CUC or both suggests that the causes of these conditions are closely related.
Scanning Electron Microscopy of the Liver Cell Cytoskeleton
Authors: Okanoue Takeshi , Ohta Masaharu , Fushiki Shinji , Ou Ongyoku , Kachi Kazutomo , Okuno Tadao , Takino Tatsuro , French Samuel W.
Published: March 2007

Rat livers were perfused with 0.5% Triton X–100 for 30 to 60 min and studied by scanning electron microscope. Three–dimensional filamentous networks were visualized in the cytoplasm of hepatocytes in situ. Branching and end–to–side contacts of intermediate filaments, and intermediate filaments which were connected with microtubules and microfilaments were noted. Numerous filaments were observed in the perinuclear region and at the cell border. Filaments were attached to polyribosomes and nuclei. No differences were observed in the cytoplasmic cytoskeleton after treatment of the sample at 4°C. These results support the concept that intermediate filaments mechanically integrate the cytoplasmic space.
Ammonia, Octanoate and A Mercaptan Depress Regeneration of Normal Rat Liver After Partial Hepatectomy
Authors: Zieve Leslie , Shekleton Michael , Lyftogt Carolyn , Draves Kay
Published: March 2007

Four injections of subcoma doses of ammonium acetate, octanoic acid or dimethyl disulfide during the first 24 hr after two–lobe hepatectomy in normal rats markedly depressed DNA synthesis as reflected by liver thymidine kinase activity or the incorporation of tritiated thymidine into hepatic DNA. Recovery from the depressant effects of the three toxins took 16 to 28 hr. Similar doses of the same toxins injected hourly for 3 or 5 hr after the two–lobe hepatectomy had similar depressant effects on the early peak of ornithine decarboxylase activity measured at 4 or 6 hr. Recovery occurred within 3 hr perhaps because of the very short half–life of ornithine decarboxylase and its rapid regeneration time. These observations may have implications for the lack of regeneration observed in many patients with fulminant hepatic failure who have accumulated sufficient ammonia, methanethiol and fatty acids over periods of days or weeks to become encephalopathic.
Immunosuppressive Treatment of Hbsag–Positive Chronic Liver Disease: Significance of Hbeag
Authors: Tage-Jensen Ulrik , Aldershvile Jan , Schlichting Poul
Published: March 2007

In a randomized clinical trial in 148 patients of azathioprine vs. prednisone treatment of chronic aggressive hepatitis and/or nonalcoholic cirrhosis, 20 were HBsAg positive on entry. In this subgroup sequential serum samples were investigated for HBs and HBe markers by radioimmunoassay. At the time of evaluation, 13 patients were still alive; their median age was 53 years (25 to 72) and median follow–up time was 46 months (23 to 82).

Of 16 patients with cirrhosis, 5 of 7 with persistence of HBeAg died, compared with 2 of 9 with anti–HBe. In three patients with anti–HBe, HBeAg reappeared several times with simultaneous rise in transaminase values.

The overall survival was 65% after 5 years. The prognosis of HBsAg–positive chronic liver disease seemed to depend on the presence of cirrhosis and HBeAg rather than on improvement in biochemical activity during immunosuppressive treatment.
Rheumatoid Factor–Like Reactants in Sera Proven to Transmit Non–A, Non–B Hepatitis: A Potential Source of False–Positive Reactions in Non–A, Non–B Assays
Authors: Shiraishi Hiroyuki , Alter Harvey J. , Feinstone Stephen M. , Purcell Robert H.
Published: March 2007

Convalescent phase non–A, non–B (NANB) human and chimpanzee sera were utilized in a solid–phase radioimmunoassay (RIA) in an attempt to identify a specific NANB antigen in human plasma, plasma–derived pellets and NP–40 disrupted pellets proven to transmit NANB infection to chimpanzees. RIA reactivity was noted in 5 of 8 pedigreed NANB infectious plasmas, but did not appear to be virus–specific. The RIA reactive fraction: (i) had a density of 1.27 to 1.32 gm per cm3 in cesium chloride; (ii) showed immunoreactivity corresponding to normal IgM, but peak RIA activity coincided with an aberrant IgM having a peak sedimentation coefficient of 56 S, and (iii) eluted at higher pH (5.6 to 5.0) than normal IgM on chromatofocusing columns. The reactant shared properties with rheumatoid factor in that it was absorbed by aggregated IgG and was unstable to 2–mercaptoethanol, but it did not react in standard agglutination tests for rheumatoid factor. The reactant was detected in both the acute and chronic phase of NANB infections in chimpanzee and man. By reacting with IgG in presumptive NANB convalescent sera, this aberrant rheumatoid factor could simulate a NANB antigen and represent a cause of false–positive reactions in putative NANB assays.
The Effects of Colchicine and Vinblastine on the Biliary Excretion of Carcinoembryonic Antigen
Authors: Thomas Peter , O'Neil Paul F. , Zamcheck Norman
Published: March 2007

The biliary output of carcinoembryonic antigen (CEA) in bile fistula rats following treatment with the microtubule poisons vinblastine and colchicine increased 3–fold over a 4–hr period. Cytochalasin B and the inactive colchicine derivative lumicolchicine had no effect. These treatments did not effect the rate of CEA clearance from the circulation. Biliary output of low molecular weight fragments from CEA degradation was decreased in the presence of colchicine and vinblastine. Mechanical obstruction of the bile duct for 3 days followed by relief of obstruction resulted in a 3–fold increased output of CEA into the bile. These results are consistent with a paracellular mechanism for CEA transport from blood to bile. Biliary duct obstruction and vinblastine and colchicine probably affect the permeability of junctional complexes between hepatocytes allowing CEA to penetrate more easily.
Severe and Progressive Steatosis and Focal Necrosis in Rat Liver Induced by Continuous Intragastric Infusion of Ethanol and Low Fat Diet
Authors: Tsukamoto Hidekazu , French Samuel W. , Benson Nancy , Delgado George , Rao Ananda G. , Larkin Edward C. , Largman Corey
Published: March 2007

Blood alcohol levels (BAL) were maintained at high levels (overall mean ± S.D. achieved in 14 alcoholic rats was 216.0 ± 120.1 mg%) in male Wistar rats for 15 to 85 days by continuous intragastric infusion of ethanol and nutritionally defined low fat liquid diet. The ethanol intake was progressively increased from 32% of total calories up to 41.4% in order to maintain high BAL. Pair–fed animals received isocaloric glucose solution and the liquid diet. Despite the low level of dietary fat (4.9% of total calories), histopathological evaluation of the liver revealed severe and progressive fatty infiltration in the alcoholic rats. In addition, following 30 days of intoxication, one third of the animals showed focal necrosis with mononuclear cell infiltration in centrilobular areas of the livers. This was correlated with the markedly elevated levels of SGOT and SGPT in these animals. Pair–fed controls showed no abnormality in the morphology of liver or blood chemistry. Chemical quantitation of liver triglycerides confirmed the histological observation, with triglyceride levels of 61.51 ± 16.45 and 89.61 ± 5.94 mg per gm at 30 and 85 days, respectively. Most importantly, the degree of steatosis was tightly and significantly correlated with the mean BAL achieved (r = 0.80, p < 0.001). These data represent the first confirmation of the hypothesis that continuously high BAL correlate with the severity of alcohol–induced liver pathology.
Temporal Relationship Between Hyperaldosteronism, Sodium Retention and Ascites Formation in Rats With Experimental Cirrhosis
Authors: Jiménez Wladimiro , Martinez-Pardo Antonio , Arroyo Vicente , Bruix Jordi , Rimola Antoni , Gaya Joan , Rivera Francisca , Rodés Joan
Published: March 2007

To investigate the role of aldosterone in sodium retention and ascites in cirrhosis, the urinary sodium excretion, sodium balance and urinary excretion of aldosterone–18–glucuronide (UAidV) were serially measured in 11 rats undergoing cirrhosis induction with carbon tetrachloride (CT) and phenobarbital (CT rats) and in 10 control rats which received phenobarbital. All CT rats developed ascites, seven within the ninth week after starting the program and four within the 10th week. One week before the onset of ascites, CT rats and control rats were different with respect to sodium excretion (1.41 ± 0.15 vs. 1.82 ± 0.1 mEq per day), sodium balance (0.57 ± 0.12 vs. 0.20 ± 0.09 mEq per day) and UAidV (67.8 ± 9.5 vs. 25.7 ± 1.7 ng per day). These differences were more pronounced within the week in which ascites was detected in CT rats. Before these 2 weeks, both groups did not differ with respect to these parameters. In the 132 urine samples obtained in CT rats, there was a correlation between sodium excretion and UAidV (r = –0.53; p < 0.001). Twenty–one additional CT rats were divided into two groups. Eleven animals were given spironolactone (20 mg per day s.c. in olive oil) from the 6th week, and 10 only received olive oil. Thirteen weeks after starting the program, all rats not treated with spironolactone had sodium retention and ascites (in five rats, ascites appeared within the ninth week and in five within the tenth week); this occurred in only one animal treated with spironolactone. This difference could not be due to a protective effect of spironolactone against carbon tetrachloride hepatotoxicity since both groups of rats were similar with respect to portal pressure and severity of hepatic lesions. These results are consistent with the concept that aldosterone plays an important but not the sole role in the pathogenesis of ascites in cirrhosis.
Pharmacokinetic–Hemodynamic Interactions Between Vasopressin and Nitroglycerin: Comparison Between Intravenous and Cutaneous Routes of Nitrate Delivery
Authors: Blei Andres T. , Friedman Steve , Gottstein Jeanne , Robertson Gary , Fung Ho-Leung
Published: March 2007

Addition of nitroglycerin (NTG) improves the hemodynamic response to vasopressin and may thus be useful in the treatment of gastrointestinal hemorrhage. We studied in the rat the influence of vasopressin on the disposition of a constant intravenous infusion of NTG and the cutaneous absorption of NTG ointment. The effect of NTG on the pharmacokinetics of vasopressin was also defermined. Animals were divided into four groups: control, NTG, vasopressin and vasopressin + NTG. Infusions (or ointments) were maintained for 70 min; cardiac output and regional blood flows were determined with the microsphere technique. Both intravenous and cutaneous NTG resulted in similar hemodynamic responses. Vasopressin caused generalized vasoconstriction, while the addition of NTG reversed the deleterious systemic hemodynamic effects of vasopressin. Addition of vasopressin to NTG did not alter NTG systemic clearance nor did NTG affect vasopressin clearance. Of note, the systemic clearance of NTG was directly correlated with the cardiac output (r = 0.804), supporting a model of NTG distribution where blood vessels and/or extrahepatic tissues are the site of elimination of the drug. The marked reduction in skin blood flow by vasopressin did not decrease the steady–state plasma concentration of NTG nor the estimated cutaneous absorption rate of NTG ointment, indicating that cutaneous blood flow is not an important determinant in the absorption of NTG ointment. The skin is an appropriate route of delivery for NTG when combined with vasopressin.
Comparison of the Phenacetin and Aminopyrine Breath Tests: Effect of Liver Disease, Inducers and Cobaltous Chloride
Authors: Schoeller Dale A. , Kotake Alvin N. , Lambert George H. , Krager Patricia S. , Baker Alfred L.
Published: March 2007

The phenacetin breath test (PBT) has been proposed as an alternative to the aminopyrine breath test (ABT) for the assessment of hepatic function. To investigate the clinical utility of the PBT, we compared the PBT with the ABT in 9 healthy subjects and 18 patients with biopsy–proven liver disease. We also investigated the effects of cytochrome P–450 inducers in humans and rats, and the effect of cobaltous chloride (CoCl2) in rats on the PBT to elucidate the relationship between the rate of phenacetin deethylation and exhaled labeled CO2 derived from phenacetin. In humans with abnormal ABTs, the PBT correlated with the ABT (r = 0.77), but in healthy humans there was no correlation between the two breath tests. Rifampin pretreatment in healthy humans induced the ABT by 27%, but did not induce the PBT. In rats the PBT was not induced by 3–methylcholanthrene pretreatment at phenacetin doses of 1 mg per kg, but was induced by both 3–methylcholanthrene (178%) and phenobarbital (142%) at 10 mg per kg phenacetin. Pretreatment of rats with CoCl2, which reduces cytochrome P–450 content, decreased the PBT by 40% and the ABT by 84%. The insensitivity of the PBT to induction except at high doses of phenacetin suggests that phenacetin deethylation is not the rate–limiting process modulating exhaled labeled CO2 in healthy subjects, and that the PBT does not generally reflect normal or induced phenacetin dealkylation rates. The PBT, however, did reflect hepatic damage and may even be better than the ABT for grading the severity of hepatic damage.
Serum β2–Microglobulin Levels in Primary Biliary Cirrhosis
Authors: Nyberg Anders , Lööf Lars , Hällgren Roger
Published: March 2007

Serum β2–microglobulin (β2μ) was determined in 44 patients with primary biliary cirrhosis (PBC) and in 63 patients with other liver disorders. β2μ levels were elevated in PBC when compared with chronic persistent hepatitis, primary sclerosing cholangitis and noncirrhotic alcohol liver disease, but not in comparison with chronic active hepatitis and alcoholic liver cirrhosis. With the exception of chronic persistent hepatitis, all liver disorders had significantly increased serum concentrations of β2μ when compared with controls. A significant correlation between β2μ and erythrocyte sedimentation rate (p < 0.001) and β2μ and serum IgG (p < 0.05) was found in PBC. No significant difference in β2μ levels was noted when PBC patients with early and late histopathological changes were compared. D–penicillamine treatment significantly (p < 0.01) but transiently reduced β2μ levels in PBC; this may reflect the presumed immunosuppressive action of this drug.
Plasma Lipoproteins and Apoproteins in Primary Biliary Cirrhosis
Authors: Koga Shunichi , Miyata Yasuji , Ibayashi Hiroshi
Published: March 2007

To elucidate abnormalities in lipid metabolism in patients with primary biliary cirrhosis (PBC), plasma lipoproteins and apoproteins were analyzed in 10 such patients. Lipoprotein X was present in sera from five of the patients. Another abnormal lipoprotein of slow α–mobility on agarose gel electrophoresis was observed in sera of eight of the patients. The slow α–lipoprotein was distributed in the range of densities between low density and high density lipoproteins and was rich in apoprotein E. This abnormal lipoprotein of PBC was observed in those in Stages II and III but not in those in Stage I. The amounts of slow α–lipoprotein correlated to the levels of serum apoprotein E and to total cholesterol. Determination of apoprotein concentrations in serum of PBC patients revealed increases of apoproteins E and C–II and a decrease of apoprotein A–II. In conclusion, lipoprotein abnormalities in PBC patients were characterized by increased levels of apoprotein E and appearance of an abnormal lipoprotein of slow α–mobility in addition to well–known lipoprotein X.