Axel Holstege

Prevalence of antibodies against hepatitis C virus in the adult German population

OBJECTIVEnThe prevalence of anti-HCV in Germany has been determined for blood donors and certain risk groups, but the burden of disease in the general population remains unknown. The aim of this study was to determine the prevalence of anti-HCV in a study group representing the normal adult German population.nnnDESIGNnA total of 5312 individuals aged 18-70 years were randomly selected from small, middle-sized and big cities in five different German states. Sera were tested for anti-HCV by enzyme immunoassay and immuno dot assay, as well as for anti-HBc and, in the case of a positive result, for anti-HBs and HBsAg. Serological typing was performed in anti-HCV-positive persons.nnnRESULTSnThirty-nine individuals were anti-HCV positive; indeterminate results (with antibodies against the viral core protein only) were obtained in 20. There was a tendency to higher prevalence rates with increasing age as well as to a higher prevalence in women. Serological typing revealed the presence of genotype 1 in the vast majority of participants (82%); only a minority showed genotype 3 (7.2%) or other genotypes (7.2%). Markers of HBV were seen in 43.6% of the anti-HCV positive individuals, with nearly one third (29.4%) of the double-infected showing anti-HBc as the only marker for HBV.nnnCONCLUSIONSnAccording to our data, an anti-HCV prevalence of 0.63% (95% confidence interval, CI, 0.42-0.84%) can be assumed in the general adult German population, with higher values in older people and women. Nearly half of the anti-HCV positive individuals also show markers of hepatitis B virus.

Brain electrical activity mapping of EEG for the diagnosis of (sub)clinical hepatic encephalopathy in chronic liver disease.

We studied the role of brain electrical activity mapping (BEAM) in the assessment of neuropsychiatric disturbances in 48 cirrhotic patients without clinical evidence of hepatic encephalopathy (no HE, n = 19), with subclinical HE (grade 0, denoting pathological psychometric tests, n = 13) and mild-to-moderate HE (grade I, n = 6; grade II, n = 10). Results were compared with 23 healthy controls. BEAM variables quantified were: (i) the peak frequency (PF); (ii) the amplitude of PF; and (iii) the topographic localization of the maximum peak amplitude digitized for quantification by using a co-ordinate system. Mean amplitudes and their topographic localization in the following frequency-bands were analysed: delta (1.0–3.5 Hz), theta (4.0–7.5 Hz), alpha 1 (8.0–9.5 Hz), alpha 2 (10.0–11.5 Hz), beta 1 (12.0–15.5 Hz), beta 2 (16.0–19.5 Hz), and beta 3 (20.0–23.5 Hz). The PF was significantly slower in all HE patients than in healthy controls (8.5 ± 2.0 Hz v. 10.1 ± 1.0 Hz, P < 0.001). Even in no HE, the PF was significantly slower than in controls (8.6 ± 1.5 Hz v. 10.1 ± 1.0 Hz, P < 0.01). No relevant topographic differences of PF were observed. The mean amplitudes of the following bands differed significantly between controls and patients: theta (increased in HE, P < 0.05), alpha 2 (decreased in HE, P < 0.05), and beta 2 and beta 3 (increased in HE, P < 0.05). In HE patients, the topographic localization of all beta bands showed a significant shift from parieto-occipital areas to central areas of the cortex. We conclude that BEAM is a sensitive tool for detecting neuropsychiatric disturbances in cirrhotics with no HE and with subclinical HE. The combination of PF in the theta band, increased mean amplitude in the beta 2 band, and the localization of the latter band in the frontocentral area of the cortex is an objective and sensitive tool for identifying neuropsychiatric disturbances in 85% of cirrhotic patients with no HE. Further studies are required to determine the clinical implications of these abnormal findings in the absence of overt clinical symptoms.

Evidence for the production of high amounts of interleukin-6 in the peritoneal cavity of patients with ascites

The ascites and serum concentrations of interleukin-6 (IL-6) and interleukin-1 (IL-1) were determined in 21 patients with hepatic ascites and in 9 patients with malignancy-associated ascites. There was no evidence for bacterial peritonitis in any patients. All ascites samples contained high amounts of immunoreactive IL-6 [hepatic ascites 1730 +/- 2130 pg/ml (mean +/- SD), 1160 pg/ml (median); malignant ascites 4020 +/- 1510 pg/ml (mean), 3820 pg/ml (median)] but no IL-1. The mean ascites to serum ratios of IL-6 were 96 (median 49) in patients with hepatic ascites and 587 (median 480) in patients with malignant ascites. Ascites IL-6 was biologically active as determined by the B9 cell bioassay. The results indicate that even in the absence of infection IL-6 is produced in high amounts in the peritoneal cavity of patients with hepatic or malignant ascites.

Increased formation of nucleotide derivatives of 5-fluorouridine in hepatoma cells treated with inhibitors of pyrimidine synthesis and D-galactosamine

Fluorinated pyrimidines and their nucleosides are widely used in the chemotherapy of tumors; their mode of action requires the formation of nucleotide derivatives (summa~ [I ] ). Uridine kinase (EC 2.7.1.48) plays a key role in the conversion of 5fluorouridine (5-FUrd) to its active metabolites. The feedback regulation of uridine kinase by UTP [2] can be used for an increase in the cell-specific uptake of some pyrimidine analogs after depletion of the cellular UTP pools [3] . Induction of selective UTP deficiency by D-galactosamine (GalN) and 6azauridine (6aza-Urd) in hepatoma cells [4] is associated with an increased formation of phosphorylated derivatives of 5-FUrd [3]. This approach [3] has the following implications: (i) Considerable selectivity for hepatoma cells and hepatocytes is based on the action of GalN [3,5] ; (ii) The increased activity of uridine kinase [6,7] and the high rate of de nova pyrimidine nucleotide synthesis in hepatoma cells relative to liver [7-IO] makes these malignant cells more susceptible to the action of 6aza-Urd. (iii) The formation and accumulation of 5-fluoxoUDP-amino sugars may serve as a metabolic store providing 5-FUrd phosphates; the latter become available in amino sugar transferase reactions or upon hydroly tic splitting of the fluorinated amino sugar nucieotide. In this communication we demonstrate the negative correlation between 5-FUrd uptake and intracellular UTP level. The replenishment of

Correlation of caffeine elimination and child's classification in liver cirrhosis

SummaryApparent pharmacokinetic parameters of caffeine elimination from the circulation were determined in 27 patients with histologically confirmed liver cirrhosis, 8 patients with miscellaneous liver disease, and 8 patients with other than liver disease. The usefullness of this quantitative test to assess the severity of liver cirrhosis was compared to the Child-Turcotte or Child-Pugh classification score as well as to the galactose elimination capacity of these patients. Using reversed-phase high pressure liquid chromatography caffeine, paraxanthine, theophylline, and theobromine were analysed in blood plasma collected before and after an oral dose of caffeine. Compared to apparent caffeine pharmacokinetics in patients with normal livers or miscellaneous liver disease, cirrhosis was characterized by a statistically significant reduction in apparent caffeine clearance and prolongation in half-life. The reduced apparent plasma disappearance rate of caffeine in cirrhotics was related to the retarded formation of paraxanthine which was the main metabolite of caffeine in blood plasma both in the absence or presence of liver disease. The apparent caffeine clearance in cirrhosis decreased with increasing Child-Turcotte classification score: Childs class A patients differed significantly from Childs class B or Childs class C patients, whereas the difference between Childs class B and C patients did not reach statistical significance (Wilcoxons rank test). In addition there was a strong correlation between the Child-Pugh classification score and apparent caffeine clearance (P<0.001). However, no correlation existed between Childs classification and galactose elimination capacity. Our data emphasize the value of the Child-Turcotte or Child-Pugh classification in assessing the severity of liver cirrhosis in a simpler and less time-consuming way than using quantitative liver function tests.

Ursodeoxycholic acid induced activation of the glucocorticoid receptor in primary rat hepatocytes.

Background and aims Ursodeoxycholic acid (UDCA), a hydrophilic bile acid, improves biochemical, immunopathological and histological parameters in chronic cholestatic liver diseases. The immunomodulatory properties of UDCA show interesting similarities with the effects of glucocorticoids. We investigated the activation of the glucocorticoid receptor by UDCA and the glucocorticoid receptor dependent gene expression in primary rat hepatocytes as well as binding of radiolabelled UDCA to the glucocorticoid receptor ligand binding site expressed in a glucocorticoid receptor fusion protein. Methods Primary rat hepatocytes in culture were co-transfected with a luciferase reporter gene construct (GRE-luc) containing a glucocorticoid receptor responsive element (GRE) and a glucocorticoid receptor expression vector (6RGR) followed by stimulation with dexamethasone or UDCA. Luciferase activity was determined and specific binding of glucocorticoid receptor to the GRE was confirmed by an electrophoretic mobility shift assay (EMSA). The glucocorticoid receptor binding site was expressed in a GR-myc fusion protein and binding of radiolabelled UDCA to the fusion protein was determined. Results Incubation of co-transfected hepatocytes with 0.1–1.000u2009μM dexamethasone or 0.1–1.000u2009μM UDCA led to an 11.9- to 20.85-fold (dexamethasone) and 2.6- to 4.3-fold (UDC) increase of luciferase activity. Mobility shift assays using nuclear extracts from transfected and stimulated hepatocytes also showed a dose dependent increase of DNA binding after stimulation with UDCA. However, incubation of the GR-myc fusion protein with radiolabelled UDCA yielded no specific binding of UDCA to the glucocorticoid receptor binding site, whereas dexamethasone showed specific binding of the fusion protein. Conclusions UDCA activates the intracellular glucocorticoid receptor in a dose-dependent manner. Direct binding of the glucocorticoid receptor by radiolabelled UDCA at the glucocorticoid receptor binding site could be excluded as the mechanism of activation. The mechanisms involved in UDCA-mediated glucocorticoid receptor activation and possible targeted glucocorticoid receptor activation due to partial UDCA tissue specificity warrant further elucidation.

Selective enhancement of 5-fluorouridine uptake and action in rat hepatomas in vivo following pretreatment with d-galactosamine and 6-azauridine or N-(phosphonacetyl)-l-aspartate☆

Abstract The sequential combination of three antipyrimidines was studied in rats carrying Morris hepatoma 7777 , the AS- 30 D ascites hepatoma, or the solid intrahepatic AS- 30 D tumor. The uptake of [14C] 5 -fluorouridine and its incorporation into RNA was selectively enhanced in hepatomas in vivo by pretreatment of the animals with d -galactosamine and an inhibitor of de novo pyrimidine synthesis, such as 6 -azauridine or N -(phosphonacetyl)- l -aspartate. This pretreatment resulted in a transient depletion of uridine phosphate pools which was the prerequisite for the subsequent increase in 5 -fluorouridine phosphorylation in the hepatoma. It was demonstrated by radio-paper chromatography that the formation of 5 -fluorouridine diphosphate N -acetylhexosamines was markedly enhanced when the pretreatment included d -galactosamine. The incorporation of labeled precursors into nucleic acids of AS- 30 D cells treated with 5 -fluorouridine indicated that a severe inhibition of thymidylate synthase was associated with only a moderate depression of DNA synthesis, as measured by incorporation into DNA of [ 3 H] deoxyuridine and [ 14 C] deoxyadenosine, respectively. Survival of rats bearing the intrahepatic or the ascites form of the AS- 30 D hepatoma was prolonged most after the sequential treatment with d -galactosamine + 6 -azauridine + 5 -fluorouridine. When 6 -azauridine was replaced in this combination by N -(phosphonacetyl)- l -aspartate, 80% of ascites hepatoma-bearing rats became tumor-free.

Case Report: Spontaneous Rupture of Liver in a Patient with Ehlers Danlos Disease Type IV

Ehlers-Danlos syndrome (EDS) type IV is an autosomal dominant connective tissue disease caused by mutations in the type III collagen gene resulting in extreme tissue fragility. Affected individuals are at risk of dramatic and often fatal complications, mostly spontaneous arterial, uterine, or colonic ruptures. Phenotypic expression of EDS type IV is variable and clinical signs are generally quite subtle, thus making a prompt diagnosis difficult. The case of a 33-year-old woman is described who presented with a wide range of clinical features and sequelae that eventually led to the diagnosis of EDS type IV. She presented with spontaneous liver rupture, renal infarction, and pneumothorax, all representing rare complications of EDS type IV. Prior history revealed a uterine rupture in advanced pregnancy associated with ischemic necrosis of the descending and sigmoid colon. EDS type IV should be suspected in young individuals who present with such unusual complications. Early diagnosis is essential if severe or even lethal complications are to be avoided in the diagnostic and therapeutic management of such patients.

Excretion of caffeine and its primary degradation products into bile

Caffeine, widely consumed in beverages, is known to alter several biliary parameters that can affect gallstone pathogenesis. To address the question whether methylxanthines can act on the luminal side of biliary epithelial cells, we measured caffeine and its primary demethylation products in human bile. Eight patients had an external biliary drainage due to bile duct or gallbladder disease. Two of the patients suffered from histologically confirmed liver cirrhosis. The levels of caffeine, paraxanthine, theobromine, and theophylline were monitored over 10 h in plasma and bile before and after a prior oral dose of caffeine (5 mg/kg b. wt.). Methylxanthines were enriched by an organic extraction procedure and separated by reversed-phase high-performance liquid chromatography. Time-concentration curves in bile paralleled the time-course of methylxanthine levels in blood plasma. Accordingly, values in bile and blood plasma were highly correlated for each methylxanthine measured. Within 1 h after the oral test dose, peak levels of caffeine were obtained in both fluids. Biliary concentrations were either almost equal (caffeine) or lower (dimethylxanthines) than their respective values in blood plasma. The results of our study indicate that minor amounts of caffeine and its primary degradation products are excreted via the bile allowing local interference with epithelial cell metabolism of bile ducts and gallbladder.

Uridine catabolism by the isolated perfused rat liver

A new approach in the treatment of gastrointestinal tumors with 5-fluorouracil involves the infusion of high doses of uridine to improve the chemotherapeutic efficiency of the former. High amounts of uracil formed from uridine can interfere with the hepatic catabolism of 5-fluorouracil and thus increase its bioavailability and toxicity. In our study, we analysed the metabolite pattern of uridine in the effluent of isolated perfused rat livers in relation to portal uridine levels. The livers were perfused hemoglobin-free without recirculation at a constant flow. In the perfusate, uridine was changed from 0.5 to 100 mumol/l. The complete degradation of [2-14C]uridine and [2-14C]uracil was monitored via the release of labeled CO2. Radioactive catabolites of uridine including uracil and the sum of dihydrouracil and beta-ureidopropionate were separated by high-performance liquid chromatography and counted using a radioactivity flow monitor. Portal uridine concentrations were increased from 0.5 to 100 mumol/l and were accompanied by a rise in the relative amount of non-metabolized uridine in the effluent from 13 to 78%. At uridine concentrations above 50 mumol/l, there was a constant release of uracil into the effluent, indicating saturation of uridine phosphorolysis or transport. The amount of 14CO2 formed by the liver reflecting complete uridine breakdown was higher than any other uridine metabolite when uridine concentration varied from 0.5 to 15 mumol/l. Saturation of 14CO2 formation was achieved at a uridine concentration of 25 mumol/l. Higher peak values of 14CO2 release were observed after direct infusion of equivalent amounts of uracil into the portal vein.(ABSTRACT TRUNCATED AT 250 WORDS)