Search PubMed⌕ Search

Biomedical subjects

J Fevery

Publications and source records attributed to J Fevery.

At least 253 records · Page 14Linked to original sources

Enhancement by secretin of the apparently maximal hepatic transport of bilirubin in the rat.

The effect of secretin (0.4 C.U. per hr per 100 gm body weight) on bile flow and the apparent maximal hepatic transport of bilirubin (Tm) was investigated in the rat. When secretin was administered during an already established bilirubin-Tm condition, it increased bile flow and bilirubin-Tm by 15 to 20% over a 30- to 50-min period. Enhancement of bilirubin output correlated with augmented flow and was sustained by an increased rate of excretion of monoglucuronides. When secretin was given for 90 min before bilirubin loading, it enhanced biliary bilirubin concentration and output, largely as diglucuronides. Bilirubin-Tm correlated positively with glururonyltransferase activity in liver homogenates. In the isolated perfused rat liver, injection of secretin in the portal cannula failed to produce choleresis. Bilirubin uridine diphosphate-glucuronyltransferase activity was lower than in intact rats and higher after treatment than in controls. The effect of secretin had an early effect on hepatocytic bile flow and a later effect on conjugation. Maximal hepatic bilirubin output was modulated both by flow and conjugation rate; the two mechanism may act independently.

Animals↗

Serum bilirubins in hepatobiliary disease: comparison with other liver function tests and changes in the postobstructive period.

Unconjugated bilirubin and its mono- and diester conjugates were measured by alkaline methanolysis and normal-phase high-performance liquid chromatography (AMHPLC) in 195 serum specimens obtained from 63 patients with various hepatobiliary disorders and from 47 healthy adult controls. With this assay, esterified bilirubins were undetectable in the controls, and detection of esterified pigment in a sample was interpreted as an abnormal result. Using this criterion, the AMHPLC result in the clinical anicteric patients (n = 39) was more frequently abnormal (87%) than the corresponding value of fasting serum bile acids (48%), SGPT (52%), total bilirubins (55%), alkaline phosphatase (71%) or gamma-glutamyl transpeptidase (71%). The cumulative frequency of abnormality of these tests was comparable to that of an abnormal AMHPLC result alone. All icteric patients had detectable esterified bilirubins as well as an increased alkaline phosphatase level, while a normal result was found for serum bile acids in 34%, for SGPT in 29% and for gamma-glutamyl transpeptidase in 11%, respectively. In most hyperbilirubinemic patients, total serum bilirubin levels, as determined by a conventional diazo method, exceeded the value obtained by AMHPLC. This discrepancy, which appears to reflect the presence of bilirubin covalently bound to serum protein, was particularly pronounced following desobstructive intervention in patients with obstructive jaundice, in whom the decline of serum bilirubins showed a fast and a slow disappearance component. The latter portion seemed to correspond with slow plasma clearance of bilirubin covalently linked to serum albumin, disappearing at a rate comparable to that of the albumin moiety.

Adolescent↗

Effects of ioglycamide on the hepatic transport of bilirubin and its mono- and diconjugates in the rat.

Bilirubin seems to share the biliary excretion pathway with other organic anions, but not with bile acids. We studied the effects of the organic anion ioglycamide, an iodinated contrast agent, on bilirubin metabolism in Wistar rats. This compound does not undergo conjugation and is characterized by a maximal biliary secretory rate (Tm). The results show that in spite of producing a 3-fold increase in bile flow, ioglycamide excretion under Tm conditions decreased the output of unconjugated bilirubin and its monoconjugate by approximately 90%. Diconjugated bilirubin decreased by only 50% and became by far the predominant pigment in bile (86.5 +/- 6.0% of total pigment vs. 61.0 +/- 4.0% in basal conditions, n = 12). Unconjugated and monoconjugated bilirubins changed in parallel suggesting that the former arises from the monoconjugates. In serum, diconjugated bilirubin augmented from trace amounts to 1.15 +/- 0.17 mumole per liter. Total conjugated pigments in serum increased from 5 to 85% of total bilirubin. Bile acid output remained unchanged. Pretreatment of rats with ioglycamide altered neither the activity of bilirubin UDP-glucuronyltransferase nor the ratio of diconjugate to monoconjugate formed at both low (25 microM) and high (164 microM) bilirubin concentrations. The observed biological effects of ioglycamide were dose-dependent and fully reversible. We suggest that ioglycamide interferes with the excretion of conjugated bilirubins ("bilirubinostasis"). The monoconjugates retained in the hepatocyte might then undergo more efficient transformation to diconjugates, the latter thus becoming the most important bile pigments in serum and bile.

Animals↗

Does ex vivo vascular resistance reflect viability of non-heart-beating donor livers?

AIMS: The use of non-heart-beating (NHB) donor livers is limited by a higher risk for primary nonfunction and the absence of methods to measure this risk. This study was designed to determine whether ex vivo vascular resistance of livers correlates with the length of warm ischemia (WI), and, thus, with viability of NHB livers. METHODS: Porcine livers were recovered after 0, 45, or 90 minutes WI. Livers were flushed by gravity and cold stored for 3 hours. Thereafter, livers were perfused at 4 degrees C. Portal vein (PV) and hepatic artery (HA) vascular resistance were calculated during liver flush-out and during 24 hours of machine perfusion. RESULTS: During flush-out, PV and HA vascular resistance were higher among livers with longer WI times; however, only in the PV did the results reach statistical significance. During machine perfusion, PV vascular resistance was low from the start and remained fairly constant. In contrast, HA vascular resistance was higher at the start but gradually diminished to reach a more constant value after 4-6 hours. No correlation was observed between HA or PV vascular resistance and WI during machine perfusion. CONCLUSIONS: The vascular resistance during ex vivo machine perfusion of NHB livers does not correlate with the extent of WI damage and, therefore, cannot predict organ viability.

Animals↗

Liver fatty acid-binding protein: an early and sensitive plasma marker of hepatocellular damage and a reliable predictor of graft viability after liver transplantation from non-heart-beating donors.

OBJECTIVE: Liver fatty acid-binding protein (L-FABP) is a small protein (15 kD) involved in the intracellular transport of long-chain fatty acids in the liver. The L-FABP is regarded as a sensitive marker for liver cell damage. In a pig model for liver transplantation (LTx) from non-heart-beating donors (NHBD), we evaluated plasma changes of L-FABP early after reperfusion of grafts exposed to increasing periods of warm ischemia (WI). METHODS: Porcine livers were procured after 0, 15, 30, 45, and 60 minutes' WI. After 4 hours' cold ischemia (CI), LTx was performed. Primary graft nonfunction (PNF) and day 4 survival were recorded. Plasma samples were collected prior to and 15, 60, and 180 minutes after graft reperfusion for determination of L-FABP and aspartate transaminase (AST). RESULTS: Early after reperfusion, levels of L-FABP correlated well with the duration of WI. The PNF developed in 100% of animals after 60 minutes of WI, 50% after 30, and 45 minutes' WI, and was absent after no WI and 15 minutes of WI. Day 4 survival was 100% in 0 minutes' WI, 83% in 15 minutes' WI, 50% in 30 and 45 minutes' WI, and 0% in 60 minutes of WI. CONCLUSIONS: Plasma levels of L-FABP correlated well with WI and concomitant hepatocellular damage in LTx from NHBD. Monitoring of posttransplant L-FABP plasma levels is a valuable new tool to quantify early the extent of parenchymal cell damage of NHBD livers and to predict their viability and function.

Animals↗

Selection criteria and outcome of patients referred to intestinal transplantation: an European center experience.

Until 1998, intestinal transplantation (SBT) had not been performed in our region of Flanders, Belgium. Potential SBT activity was not known and selection criteria had not been validated. A multidisciplinary SBT program was launched in 1998. We analyzed requests for SBT and outcomes in these patients whether with or without SBT. Listing for SBT was only considered for patients with irreversible short bowel syndrome who had developed life-threatening complications of total parenteral nutrition, but whose general condition was still thought compatible with surgery and immunosuppression. During the study period 1998 to 2004, one third of the requests for SBT (10/31) were deemed suitable. SBT in this group was lifesaving (100% survival) when performed in time. Mortality in this group without SBT was high (67%). Two thirds of the patients (21/31) did not fulfill the SBT inclusion criteria, either because they were "too moribund" to tolerate transplantation or because they were "too well". This preliminary study emphasized the importance of (1) early referral of potential SBT candidates, (2) adherence to strict criteria for listing patients for SBT, and (3) referral of intestinal donors to procurement organizations.

Adult↗

CT demonstration of right hepatic lobe atrophy.

Postoperative bile duct obstruction with subsequent stone formation and infection led to atrophy of the ipsilateral lobe and portal vein obstruction, which promoted further atrophic changes. The compensatory increase in hepatic arterial blood flow resulted in an early enhancement of the atrophic lobe on CT after intravenous contrast medium injection.

Atrophy↗

Noniatrogenic haemochromatosis in congenital dyserythropoietic anaemia type II is not related to C282Y and H63D mutations in the HFE gene: report on two brothers.

BACKGROUND: The discovery of the gene responsible for most cases of hereditary haemochromatosis has made it possible to evaluate the role of this gene in iron accumulation in other conditions. Previous observations in patients with various inherited anaemias are suggestive of a role of the haemochromatosis gene in the noniatrogenic form of iron overload that may occur in these conditions. METHODS: We studied two brothers with congenital dyserythropoietic anaemia type II, presenting with marked noniatrogenic iron overload. Young age, familial occurrence, concordance of iron overload, and histology were all suggestive of a genetic basis for the iron overload. A search for C282Y, H63D, S65C, and IVS3 + 1G?T mutations was performed by polymerase chain reaction after extraction of genomic DNA from whole blood. RESULTS: A search for the C282Y, H63D, S65C, and IVS3 + 1G?T mutations in the HFE gene proved to be negative. Despite the existence of ineffective erythropoiesis with mild anaemia, both patients were treated with regular phlebotomies in order to prevent long-term complications of their iron-overload. This treatment was well tolerated. CONCLUSIONS: 1. C282Y, H63D, S65C, and IVS3 + 1G?T mutations were negative in two brothers with congenital dyserythropoietic anaemia, in whom young age, familial occurrence, concordance of iron overload, and the histological pattern were all suggestive of hereditary haemochromatosis. 2. Treatment with regular phlebotomies, in order to prevent complications of iron overload, was well tolerated despite the existence of mild haemolytic anaemia.

Adult↗

Questionnaires are better than laboratory tests to screen for current alcohol abuse or dependence in a male inpatient population.

OBJECTIVE: To assess the diagnostic performance of the CAGE and AUDIT (Alcohol Use Disorder Identification Test) and its derivatives, and laboratory tests for screening alcohol abuse or dependence in a male medical hospital population. DESIGN: A diagnostic cross-sectional prevalence study. SETTING: Three general hospitals and one university hospital. PATIENTS: All male patients older than 18 years admitted to the hospitals, during a period of 6 weeks, were consecutively included in the study (N = 233). MEASUREMENTS: Calculation of diagnostic measurements with 95% CI and ROC curves for different scores of CAGE, AUDIT and derivatives, laboratory tests and % Carbohydrate Deficient Transferrin (CDT), using DSM-III-R as the reference standard, derived from the CIDI. RESULTS: A current diagnosis of alcohol abuse or dependence was found in 29 medical male inpatients, representing 12.4% (95% CI: 8.6-17.5). Ten of these (4.2%) fulfilled criteria of alcohol abuse and 19 (8.2%) the criteria of alcohol dependence. Laboratory tests are useless as screening tools with sensitivities between 10% (%CDT) and 52% (GammaGT). Only the Fiveshot questionnaire seems to yield reasonable diagnostic parameters at the recommended cutpoint of > or = 2.5 with a sensitivity of 79.3% and a specificity of 87.7%. CONCLUSIONS: With a prevalence of 12.4%, our results are similar with other published studies for alcohol abuse and dependence according DSM criteria. The AUDIT as well as the Fiveshot seems to have the best diagnostic properties in this male medical inpatient population, and regarding to brief interventions, these questionnaires can be used as screening instruments as well as opportunities to talk about alcohol problems with admitted patients.

Adult↗

Glucagon enhances bile flow, bilirubin uridine diphosphate-glucuronyltransferase activity and biliary bilirubin monoconjugate excretion in the rat.

Intravenous infusion of glucagon (100 micrograms/hr/100 g body weight) in rats produces a 20 to 35% increase in bile flow and enhances the activity of hepatic bilirubin uridine diphosphate-glucuronyltransferase to 132% after a 90 min infusion. When a bilirubin load is given to produce a constant and apparently maximal biliary bilirubin excretion rate (or transport maximum) the administration of glucagon increased the bilirubin transport maximum. The excretion rate of bilirubin monoglucuronides was more enhanced than that of diglucuronide. The enhanced rate of glucuronidation, assayed in vitro, correlated with the augmented biliary output and inversely with the plasma unconjugated bilirubin levels. It is concluded that glucagon, at the dosage used, leads to a higher formation rate of bilirubin monoconjugates and that the choleresis, also induced by the hormone, enhances the biliary secretion of the monoconjugates formed. The enhanced conjugation results in a decreased plasma concentration of unconjugated bile pigment and the associated choleresis leads to a decreased di- to monoconjugate ratio, opposite to what has been observed during bilirubinostasis and cholestasis. The secretory efficacy, as assessed from the bile-to-plasma concentration ratio, is enhanced for all bilirubin pigments after glucagon administration.

Animals↗

Is HBV genotyping of clinical relevance?

The hepatitis B virus, as is the case of the hepatitis C virus, can be categorized in several genotypes. The genotyping of HBV is based on the nucleotide sequence divergence encoding the amino acids constituting the HBV surface proteins. Since the genotype of the hepatitis C virus is shown to be related to epidemiology and response to interferon therapy, one wonders whether this also holds for the hepatitis B virus. HBV genotypes clearly are found to be different in various geographical areas of infection. In Europe, genotypes A and D are predominant, whereas in Asian patients genotypes B and C are more frequent, and in the Middle-East the genotype D. Data concerning the clinical relevance are less clear but it seems that in Europe, the genotype A has a higher HBeAg clearance rate and a better outcome. In Asia, genotype B (and especially the genotype Bj) is associated with a higher HBeAg clearance and with less development of cirrhosis and HCC. The impact on spontaneous or therapy induced viral resolution is not yet clearly identified. Further evaluation in different countries is needed to delineate the impact of the genotype relative to other factors such as age at infection, level of serum transaminases and viral load, on the course of infection, complication, outcome of treatment and prognosis.

Antiviral Agents↗