Transformation of 5-hydroperoxyeicosatetraenoic acid into dihydroxy- and cysteinyl-leukotrienes by rat hepatocytes: effects of glutathione.

In the presence of glutathione (GSH 400 microM), rat hepatocyte homogenates converted 5-hydroperoxyeicosatetraenoic acid (5-HPETE), via the intermediate leukotriene A4, into leukotriene C4 (LTC4) and leukotriene B4 (LTB4); 5-hydroxyeicosatetraenoic acid (5-HETE) was also a prominent product. During a 5-min incubation with 100 microM (13.4 microgram) 5-HPETE, 0.

Halothane metabolism: Kupffer cells carry and partially process trifluoroacetylated protein adducts.

Kupffer cells, prepared 18 h after pretreatment of rats with a single dose of halothane, did carry TFA-adducts which were recognized on Western blots by a anti-TFA-antibody. Based on apparent molecular weight, the pattern of the major TFA-adducts within Kupffer cells was similar to that observed in hepatocytes. When kept in primary culture, Kupffer cells processed TFA-adducts of apparent molecular weight of 220 kD, 110 kD and 74 kD within 24 or 48 h; in contrast, other TFA-adducts were persistent for at least 48 h in Kupffer cells.

Neonatal echovirus encephalitis with white matter necrosis.

The authors report a case of neonatal echovirus encephalitis associated with white matter necrosis. The pattern of illness in the neonatal period was diphasic, marked by hyperthermia and the occurrence of seizures. Echovirus was recovered from the cerebrospinal fluid.

Single-step organic extraction of leukotrienes and related compounds and their simultaneous analysis by high-performance liquid chromatography.

A method for the simultaneous single-step organic extraction from biological matrices of peptido- and dihydroxyleukotrienes as well as 5-hydroperoxy- and 5-hydroxyeicosatetraenoic acid followed by separation and quantitation in a single run on reversed-phase high-performance liquid chromatography was evaluated. Using an extraction system comprising 400/1200/4800 (v/v/v) aqueous phase/isopropanol/dichloromethane, pH 3.0, absolute recoveries of 82.

Properties of enzymes in hepatocytes that convert 5-HPETE or LTA4 into LTB4.

Rat hepatocyte homogenates convert 5-hydroperoxyeicosatetraenoic acid (5-HPETE) into biologically active leukotriene B4 (LTB4) as well as less active all-trans-LTB4 (i.e., 6-trans-LTB4 and 6-trans-12-epi-LTB4).

[In vitro demonstration of a deficit in suppressor T-cell function in alcoholic cirrhosis. Role of hepatitis B virus infection].

The T lymphocyte suppressor cell activity has been evaluated in 33 alcoholic patients compared with 16 normal controls, using an in vitro test. Suppressor T cells were activated with concanavalin A, and suppressor effect was quantified by the inhibition of an autologous B cell culture response to Pokeweed Mitogen. When compared with controls, cirrhotic patients showed a significant defect of suppressor cell activity on B cell production of IgG (20 +/- 3 vs 46 +/- 5 p.

Conversion of 5-hydroperoxyeicosatetraenoic acid into leukotriene B4 by rat hepatocytes: a novel cellular source for leukotriene B4.

Rat hepatocyte homogenates converted 5-hydroperoxyeicosatetraenoic acid into leukotriene B4 (LTB4). The reaction was dependent on time and protein and substrate concentration, did not require NADPH or oxygen, and was not supported by heat-inactivated hepatocyte homogenates. The authenticity of the biologically generated LTB4 that eluted at the position of synthetic LTB4 during high performance liquid chromatography was established by UV spectrophotometry, mass spectral analysis, radioimmunoassay, and a LTB4 receptor displacement assay.

Leukotriene biosynthesis: direct chemical ionization mass spectrometry of underivatized arachidonic acid metabolites.

An improved direct chemical ionization (DCI) mass spectrometric technique, using a polyimide-coated fused silica fiber as an extended probe tip, was used to obtain molecular ions and diagnostic fragment ions of underivatized arachidonic acid, 5-hydroperoxyeicosatetraenoic acid, 15-hydroperoxyeicosatetraenoic acid, leukotriene B4 (LTB4) and, for the first time, of leukotriene A4 (LTA4)-free acid. In this technique, sample compounds are coated onto the fused silica fiber and vaporized in the plume of the reagent gas plasma of a chemical ionization source without external heating of the probe. Both ammonia and isobutane DCI spectra were obtained for each compound.

[Meningomyocarditis caused by Coxsackie virus B4 in perinatology. Value of anti-Coxsackie virus B IgM].

The authors report a case of meningocarditis in a neonate caused by a Coxsackie virus B4. Outcome was favorable. Diagnosis was possible by detecting Coxsackie B4 specific IgM using an ELISA test with the sera of the infant and his mother.

Conversion of leukotriene A4 to leukotriene B4: catalysis by human liver microsomes under anaerobic conditions.

During a 2-min incubation of leukotriene A4 (LTA4) with human liver microsomes, 1.7 mol% was converted into leukotriene B4 (LTB4). The reaction was dependent on protein concentration, time, and substrate concentration, was not supported by heat-inactivated microsomes, and did not require NADPH.

[Determination of sub-populations of circulating T lymphocytes in alcoholic cirrhosis using monoclonal antibodies OKT3, 4, 5, Leu 2 and Leu 15. Effect of hepatitis B virus infection].

Peripheral T lymphocyte subpopulations were quantified in 24 alcoholic cirrhotic patients, 11 of them having anti-HBs and/or anti-HBc antibodies, and were compared with 35 healthy control subjects, 10 of them having anti-HBs and/or anti-HBc antibodies. The monoclonal antibodies utilized (OKT3, OKT4, OKT8 in simple staining, Leu 2 and Leu 15 in double staining) are considered as markers of mature (CD3), helper (CD4), cytotoxic/suppressor (CD8, Leu 2), suppressor (Leu [2+ 15+), and cytotoxic (Leu 2+ 15-) T cells. In cirrhotics, when compared to controls, the number of CD3 cells was reduced (p less than 0.

[Chickenpox and pregnancy. Perinatal aspects and prevention].

Five neonates born to women who had had varicella late in pregnancy or in the post-partum were admitted to our unit during the last year. In utero transmission of varicella-zoster virus occurred in 2 cases. One of them had no clinical eruption but specific IgM at a titer of 1/200.

High-performance liquid chromatographic assays for bufuralol 1'-hydroxylase, debrisoquine 4-hydroxylase, and dextromethorphan O-demethylase in microsomes and purified cytochrome P-450 isozymes of human liver.

Bufuralol, debrisoquine, and dextromethorphan are three prototype substrates of the common genetic deficiency of oxidative drug metabolism in man known as debrisoquine/sparteine-type polymorphism. We describe assays for the in vitro metabolism of (+)- and (-)-bufuralol, debrisoquine, and dextromethorphan in human liver microsomes and reconstituted purified cytochrome P-450 isozymes. These assays combine nonextractive sample preparation by precipitation of protein with perchloric acid with reversed-phase inorganic ion-pair HPLC and fluorescence detection.

The Kupffer cell is the first target in ricin-induced hepatitis.

The first target of ricin in the liver appears to be the Kupffer cells which are heavily damaged as early as four hours after the intravenous inoculation of 6 LD100 into mice. At that time, the only endothelial cell damage is constituted by more or less extended interruptions of the fenestrated cytoplasm. Hepatocyte injury affects the endoplasmic reticulum, the glycogen, the mitochondria as well as the plasmic membrane; however, it never results in cytolysis or complete necrosis.

Reduction of the observed prevalence of so-called non-A non-B hepatitis using sensitive markers of HBV and herpes viruses infections.

In the absence of a specific marker, the observed prevalence of so called non-A non-B hepatitis depends on the sensitivity of the markers of the other viral infections known to induce hepatitis. We have reevaluated this prevalence after using sensitive markers of HBV (HBs monoclonal radioimmunoassay M-RIA and IgM anti-HBc), EBV (IgM anti-VCA), CMV (IgM anti-CMV) and HSV (IgM anti-HSV) in a group of 53 subjects usually considered as having acute or chronic hepatitis. Detection of IgM against HBc, CMV and HSV used immunocapture tests.

Quantification of 5- and 15-HPETE's by direct chemical ionization mass spectrometry.

This report describes the application of direct chemical ionization mass spectrometry (DCIMS) to the identification and quantification of 5- and 15-HPETEs. A unique feature of the method is use of a polyimide-coated fused silica fiber that allows vaporization of the hydroperoxides, with very low excess energy, into the plume of the chemical ionization reagent gas plasma. Mass spectra are obtained that allow identification of the nonreduced and nonderivatized free acid forms of 5- and 15-HPETE as well as their quantification from 1 microgram to 100 picograms.

Alcohol-induced bone marrow damage. A bone marrow study in alcohol-dependent individuals.

Bone marrow biopsies from 30 alcohol-dependent individuals hospitalized for detoxification were investigated. Typical alcohol-induced bone marrow changes were found and served to define alcohol-induced bone marrow damage as a nosological entity. The findings took the form of heightened ineffective erythropoiesis associated with impaired iron utilization, vacuolated proerythroblasts, multinuclear erythroblasts, megaloblasts and iron-containing plasma cells as well as vacuolated precursor cells of the granulocytopoietic series.

Mephenytoin-type polymorphism of drug oxidation: purification and characterization of a human liver cytochrome P-450 isozyme catalyzing microsomal mephenytoin hydroxylation.

A genetic polymorphism causing deficient metabolism of the anticonvulsant drug mephenytoin occurs in 5% of the Caucasian and 23% of the Japanese population. By monitoring the activities of the two major oxidative pathways of mephenytoin metabolism in the column eluates, we have purified from human livers a cytochrome P-450 isozyme, P-450 meph, which exclusively and stereoselectively catalyzes the 4-hydroxylation of (S)-mephenytoin, the major pathway affected by the polymorphism, whereas P-450 meph was virtually devoid of catalytic activity for N-demethylation of mephenytoin, the pathway remaining unaffected by the genetic deficiency. P-450 meph had an apparent Mr of 55 000 and a lambda max in the reduced CO-binding spectrum of 450 nm.

Oxygen concentration-dependent metabolism of leukotriene B4 by hepatocyte monolayers.

Leukotriene B4 was found to be metabolized by rat hepatocyte monolayers at a rate that was linear with increasing substrate concentration from 74 to 740 nM leukotriene B4. The rates of metabolism were dependent on the O2 concentration and were 315, 213, 80, and 36 pmol leukotriene B4 per min per nmol cytochrome P-450 at 20% (212 microM), 4% (42.5 microM), 2% (21.

Debrisoquine/sparteine-type polymorphism of drug oxidation. Purification and characterization of two functionally different human liver cytochrome P-450 isozymes involved in impaired hydroxylation of the prototype substrate bufuralol.

The debrisoquine/sparteine-type polymorphism of drug oxidation presumably is caused by the absence or deficiency of cytochrome P-450 (P-450) isozyme(s). Using bufuralol 1'-hydroxylation as a prototype reaction of this polymorphism, two functionally distinct forms, P-450 buf I and P-450 buf II, with identical apparent Mr of 50,000 were purified from liver microsomes of three different human livers. P-450 buf I exhibited a marked selectivity for the (+)-enantiomer of bufuralol ((-)/(+) ratio = 0.

Relationships between 34 HLA-A, HLA-B and HLA-DR antigens and three serological markers of viral infections in alcoholic cirrhosis.

In order to study the genetic risk of alcoholic cirrhosis, the frequency of 26 HLA-A and -B antigens was compared in 184 normal controls, 175 alcoholic cirrhotic patients and 83 alcoholic patients with hepatic steatosis of carefully selected ethnic origin. Eight HLA-DR antigens were also determined in 95 subjects of the normal control group and 63 patients of the alcoholic cirrhosis group. The incidence of hepatitis B virus antibodies (anti-HBc and anti-HBs) was defined in 74 patients of the alcoholic steatosis group, 170 patients of the alcoholic cirrhosis group and 111 normal controls different from the previously mentioned normal control group.

The molecular mechanisms of two common polymorphisms of drug oxidation--evidence for functional changes in cytochrome P-450 isozymes catalysing bufuralol and mephenytoin oxidation.

Using the stereospecific metabolism of (+)- and (-)-bufuralol and (+)- and (-)-metoprolol as model reactions, we have characterized the enzymic deficiency of the debrisoquine/sparteine-type polymorphism by comparing kinetic data of subjects in vivo with their microsomal activities in vitro and with reconstituted activities of cytochrome P-450 isozymes purified from human liver. The metabolism of bufuralol in liver microsomes of in vivo phenotyped 'poor metabolizers' of debrisoquine and/or sparteine is characterized by a marked increase in Km, a decrease in Vmax and a virtual loss of the stereoselectivity of the reaction. These parameters apparently allow the 'phenotyping' of microsomes in vitro.