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D Larrey

Publications and source records attributed to D Larrey.

215 records · Page 12Linked to original sources
PubMedDate not supplied

Inhibition of the mitochondrial oxidation of fatty acids by tetracycline in mice and in man: possible role in microvesicular steatosis induced by this antibiotic.

Intravenous administration of high doses of tetracycline may produce severe microvesicular steatosis of the liver in man. A similar disease is observed after ingestion of drugs which inhibit hepatic mitochondrial fatty acid beta-oxidation and in subjects with various inborn defects in this metabolic pathway. We therefore determined the effects of tetracycline on the mitochondrial oxidation of fatty acids in mice and in man. In vitro, addition of tetracycline 0.25, 0.5, 1 or 2 mM inhibited by 15, 38, 56 and 65%, respectively, the formation of beta-oxidation products during incubation of palmitic acid with mouse liver mitochondria and the various cofactors necessary for beta-oxidation. Inhibition was reversible. Inhibition appeared even greater with human liver mitochondria. Tricarboxylic acid cycle activity, assessed by the in vitro formation of [14C]CO2 from [1-14C]acetylcoenzyme A by mouse liver mitochondria, was inhibited by 25, 32 and 43%, respectively, in the presence of 0.5, 1 or 2 mM of tetracycline. In vivo, administration of tetracycline, 0.25 or 1 mmole per kg, inhibited by 53 and 84%, respectively, the exhalation of [14C]CO2 during the first 3 hours following the administration of a tracer dose of [U-14C]palmitic acid. Administration of tetracycline, 0.0625, 0.25 or 1 mmole per kg, 6 hr before the measurement, increased hepatic triglycerides by 100, 170 and 250%, respectively. After 1 mmole per kg, accumulation of hepatic triglycerides was maximum at 24 hr, reaching 9-fold the control value; liver histology showed microvesicular steatosis at 6 and 24 hr. We conclude that tetracycline inhibits the mitochondrial oxidation of fatty acids in mice and in man.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
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Transferrin receptor-2 gene and non-C282Y homozygous patients with hemochromatosis.

More than 80% of the patients affected by hereditary hemochromatosis, a common inherited iron disorder, are homozygotes for the 845G --> A (C282Y) mutation of the HFE gene. However, depending on the population, 10-20% of hereditary hemochromatosis can be linked either to other HFE genotypes, particularly the compound heterozygous state for C282Y and the 187 C --> G (H63D) mutation, or to mutations of new other genes. Recently, Camaschella et al. (Nat. Genet. 25, 14-15, 2000) identified a stop mutation (exon 6 nt 750 C --> T, Y250X) on the transferrin receptor-2 (TFR2) gene in two unrelated Sicilian families with hereditary hemochromatosis. The TFR2 gene is a transferrin receptor gene homologue that seems to be involved in iron metabolism. Moreover, one of the patients described by Camaschella et al. was a H63D homozygote. H63D homozygosity can be associated with various phenotypes from asymptomatic subjects to patients with a typical form of hereditary hemochromatosis. Thus, the Y250X mutation could be the molecular defect responsible for hereditary hemochromatosis in subjects with atypical HFE genotypes. We have searched for the Y250X mutation in 63 unrelated French subjects. Forty-three had a diagnosis of hereditary hemochromatosis based on classical criteria. This group included 12 H63D homozygotes, 3 C282Y heterozygotes, and 3 patients with none of the two most prevalent HFE mutants. These 18 patients had no other HFE sequence change and were subsequently subjected to DNA sequencing of the 15 last exons and flanking sequences of the TFR2 gene. The 25 remaining hereditary hemochromatosis patients who were tested for the Y250X mutant were compound heterozygotes for the C282Y and H63D mutations. Finally, we also tested for this TFR2 mutation 20 H63D homozygotes with milder manifestations of iron overload and no acquired cause of iron overload. None of the 63 tested subjects had the Y250X mutation. Concurrently, none of the 18 hereditary hemochromatosis patients who had their TFR2 gene sequenced had any deleterious mutation. Thus, TFR2 mutations are not responsible for hemochromatosis in non-C282Y homozygous patients of our area.

Adult↗
PubMedDate not supplied

[Hepatitis caused by cyproheptadine (Periactine). A case and review of the literature].

We report the case of a patient who developed jaundice after receiving cyproheptadine for 29 days. Complete recovery occurred within 3 months after cyproheptadine withdrawal. Analysis of 3 previously reported cases and this observation shows that cyproheptadine-induced hepatitis is uncommon. Hepatitis occurs within the first month of treatment and is of the cytolytic or mixed-pattern type. Jaundice is constant. Most often, recovery occurs quickly after the discontinuation of cyproheptadine. However, acute hepatitis can be followed by prolonged anicteric cholestasis.

Adult↗
PubMedDate not supplied

Human hepatic cytochrome P-450 composition as probed by in vitro microsomal metabolism of warfarin.

Human liver microsomal fractions from 27 renal donors (tissue obtained post mortem) and from six cancer patients (tissue obtained during surgery) were used to investigate human hepatic cytochrome P-450 isozyme compositions. In vitro microsomal metabolism of the R and S enantiomers of warfarin to dehydrowarfarin and 4'-, 6-, 7-, 8-, and 10-hydroxywarfarin is catalyzed by cytochrome P-450 isozymes and was used as the basis for evaluating similarities and differences between human cytochrome P-450 isozyme compositions. The mean hepatic cytochrome P-450 concentration from postmortem samples was not significantly different from that of surgical patients (0.51 +/- 0.16 vs. 0.35 +/- 0.14 nmol/mg protein), but the NADPH-cytochrome P-450 reductase activity of the former was significantly higher than that of the latter (141 +/- 56 vs. 29 +/- 6 nmol cytochrome c reduced/min/mg protein). In general, the microsomal preparations were overall stereoselective for R warfarin metabolism. The stereoselectivities for formation of the individual metabolites of the R enantiomer were 6-, 8-, and 10-hydroxywarfarin and the S enantiomer were 4'- and 7-hydroxywarfarin. Of the 33 microsomal preparations, 21 exhibited qualitatively similar warfarin metabolite profiles with 6R- and 7S-hydroxywarfarin having the highest formation rates. Some of the preparations exhibited markedly different metabolite profiles, the most notable having 10R-hydroxywarfarin as the major metabolite. Based on the known warfarin metabolite profiles of five purified cytochrome P-450 isozymes, the isozyme composition of the microsomes can be estimated. The majority of the microsomal preparations apparently had similar isozyme compositions but some preparations were markedly different.

Adult↗
PubMedDate not supplied

[Treatment of acute alcoholic alcoholism].

Acute alcoholic hepatitis is the first alcoholic lesion of the liver in the process of progression to cirrhosis. It is due to the toxic action of alcohol on hepatocytes, in particular in the centrolobular region. It may affect a liver which is the site of fatty infiltration, fibrosis or cirrhosis, i.e. during all the stages of alcoholic liver disease. Its severity depends upon the degree of alcoholic intoxication. It may be fatal by malignant hepatic failure in a quarter of cases or, at the extreme, be totally asymptomatic. The aims of treatment are: 1) in the immediate, to prevent death; 2) subsequently, to prevent progression to cirrhosis. The majority of the wide range of treatments suggested have been evaluated in controlled trials. It is thus easy to show that corticosteroids are effective in severe acute alcoholic hepatitis, i.e. with encephalopathy and coagulation disturbances, but no in ordinary forms. Although logical, nutritional supplements, whether enteral or parenteral, have no influence on the course of acute alcoholic hepatitis. The same applies to anabolic steroids, the association insulin-glucagon, antifibrosis agents or "hepatoprotectors". The elimination of alcoholic intoxication remains the most important point, accepted by all hepatologists.

Acute Disease↗
PubMedDate not supplied

[Extrahepatic cancer in cirrhosis patients. A retrospective clinical study of 164 diagnosed cancers in 2060 cirrhosis patients].

A retrospective study of 2060 inpatients with cirrhosis of the liver identified 164 patients with extrahepatic cancer, a 20-fold increase over the expected number. Gastrointestinal, ENT, pulmonary, and hematologic malignancies predominated. Extrahepatic cancers occur more often and at an earlier age in patients with cirrhosis of the liver than in the population at large.

Adult↗