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J J Beraud

Publications and source records attributed to J J Beraud.

At least 19 recordsLinked to original sources
PubMed2004

Mechanism of in vitro heme-induced LDL oxidation: effects of antioxidants.

BACKGROUND: Heme protein toxicity, owing to generation of reactive oxygen species most likely by direct interaction between heme iron and hydrogen peroxide (H2O2), may be involved in various pathologies, including atherogenesis and pigmentary acute renal failure. The aim of this study was to investigate the mechanism of heme cytotoxicity and the effects of antioxidant therapies in an in vitro model of heme-induced low-density lipoprotein (LDL) oxidation. MATERIALS AND METHODS: Human LDLs were exposed to heme, iron (Fe), protoporphyrin (PPIX) and PPIX-Zinc (Zn) with or without H2O2. Lipid peroxidation was monitored by measurement of conjugated diene formation (at the 234-nm absorbance). The effect of various antioxidants, such as vitamin E and vitamin C, reduced glutathione (GSH), and oxidized glutathione (GSSG), mannitol and desferoxamine (DFO) was further investigated in the established in vitro model of LDL oxidation. RESULTS: Incubation of LDLs in the presence of heme/H2O2 induced lipid peroxidation with the optimal oxidation rate being at 5 microm heme/100 microm H2O2 doses. By contrast, incubation of LDL with H2O2, Fe, Fe/H2O2, PPIX, PPIX/H2O2, heme or PPIX-Zn did not initiate any LDL oxidation. In vitro, the vitamin E load protected native LDLs against heme/H2O2 oxidative modifications. Incubation of LDLs with increasing doses of vitamin C, GSH and DFO conferred a dose-dependent protection, while mannitol and GSSG had no effect. CONCLUSIONS: Initiation and propagation of heme-induced lipid peroxidation is not mediated by a Fenton reaction but depends on specific interactions between heme and H2O2. It may result from the generation of ferryl and perferryl radicals derived from hemic Fe and H2O2 interactions. A protective effect of vitamins E, C, GSH and DFO was demonstrated in this model.

Antioxidants↗
PubMed1996

Nephrotic syndrome associated with chronic lymphocytic leukemia resistant to immunosuppressive drugs: remission obtained by splenectomy.

Chronic lymphocytic leukemia is a common disease in the elderly but is rarely associated with a nephrotic syndrome. The rarity of this association suggests that leukemic cells may have certain properties or features that may lead to the development of glomerulonephritis. Effective medical treatment of the leukemia may not necessarily allow regression of the nephrotic syndrome; however, the effects of splenectomy on nephrotic proteinuria when associated to chronic lymphocytic leukemia have never been evaluated. We report the case of a 50-year-old male with stage C CD5+ chronic lymphocytic leukemia associated with a nephrotic syndrome due to Type I membranoproliferative glomerulonephritis. Chlorambucil and prednisone were unable to control the leukemia and the nephrotic range proteinuria, and were discontinued because of poor hematologic tolerance. A splenectomy immediately resulted in a spectacular remission of both chronic lymphocytic leukemia and the nephrotic syndrome. Spleen lymphocytes were collected and tested in quantitative flow cytometry for the expression of the main B cell associated markers. They did not exhibit any particular immunophenotypic pattern. This report of a remission of a glomerulonephritis associated with chronic leukemia following splenectomy is evidence of a possible relationship between the two diseases.

Glomerulonephritis, Membranoproliferative↗
PubMed1995

Prognosis of acute renal failure in the elderly.

UNLABELLED: Life expectancy is uncertain in the elderly with ARF. In order to determine whether a costly supportive management is worthwhile, we have studied a group of 68 elderly patients (over 65 years of age) admitted to the ICU with ARF. PATIENTS: 47 male; 21 female; 72 +/- 6 years old. Types of ARF include prerenal 24; obstructive 9; intrinsic 35 (acute tubular necrosis 30; glomerulonephritis 4; vascular 1). The mean simplified acute physiology score (SAPS) was 14 +/- 4; 39 patients (57.3%) had more than two underlying diseases; 42 patients (61.7%) were on mechanical ventilation; 40 patients (60%) underwent haemodialysis. The overall survival rate was 36.7%. Among the parameters studied, organic systemic failure index (OSF), diuresis, blood lactate, systolic blood pressure, urea appearance rate (UAR), differed significantly in survivors and deceased. From these results we conclude that the elderly with non-oliguric ARF, normal blood lactate, low catabolic state, and no more than two organ failures have a fair chance of recovering and should therefore be treated aggressively. In other cases, decisions to proceed with intensive supportive measures should be made according to individual characteristics.

Acute Kidney Injury↗
PubMed1989

Failure to achieve tight control of plasma cholesterol and apolipoprotein B with intraperitoneal insulin infusion in type 1 diabetes.

The best route of insulin administration by infusion pumps remains a subject of controversy. For that reason plasma lipids and apolipoproteins were compared in three groups of nine patients who had been treated for several months or years with conventional treatment (group I), continuous subcutaneous insulin infusion (CSII, group II) or continuous intraperitoneal insulin infusion (CPII, group III). Plasma cholesterol and apolipoprotein B remained increased on CPII compared with CSII even when similar satisfactory or even tight diabetic control was achieved with both techniques. This study suggests that cholesterol and perhaps apolipoprotein B biosynthesis by the liver is increased in patients treated with CPII compared to those treated with CSII.

Adult↗
PubMed1989

Reversal of acute renal failure following percutaneous transluminal recanalization of an atherosclerotic renal artery occlusion.

Thrombosis of the renal artery to a single functioning kidney is a known cause of anuric acute renal failure in atherosclerotic hypertensive patients. In the present report, recovery of renal function rapidly occurred following transluminal recanalization of the occluded artery with a 7F catheter after a 5-week period of anuria. The most interesting feature was that improvement of renal artery permeability was observed following a minimal interventional procedure.

Acute Kidney Injury↗
PubMed1986

Internal jugular vein cannulation with two silicone rubber catheters: a new and safe temporary vascular access for hemodialysis. Thirty months' experience.

Temporary and immediately usable vascular access is a vital need in treating uremic patients. Subclavian vein cannulation, although a major progress, has been associated with significant morbidity and mortality. Accordingly, for the last 2.5 years the authors have been developing an alternative technique consisting of internal jugular vein cannulation (IJVC) with two silicone rubber catheters with a long-term, proved biocompatibility. One hundred sixty-five pairs of cannulas were inserted in 153 patients. Mean duration of use was 57 days (1 day to 17 months). More than 3,000 high-performance hemodialysis sessions were performed. IJVC handling and care were easily managed by nurses. A low incidence of complications was observed: two thrombosis episodes, four skin infections with three septicemia, one air embolism, and one anaphylactoid reaction. No death was related to the technique itself. IJVC offers a new, safe, and reliable temporary vascular access immediately usable for all kinds of extracorporeal treatment.

Aged↗
PubMed1986

Internal jugular vein cannulation using 2 silastic catheters. A new, simple and safe long-term vascular access for extracorporeal treatment.

Subclavian vein cannulation, although a major progress in temporary vascular access, was associated with a significant morbidity and mortality. A safer alternative technique would therefore be welcome. For the last 2 years, we developed a new approach consisting in internal jugular vein cannulation (IJVC) with 2 silicone rubber catheters with a long-term proved biocompatibility. 138 pairs of cannulae were inserted in 129 uremics patients. Mean duration of use was 54 days (1 day to 17 months). More than 3,000 high-performance HD sessions were performed. IJVC handling and care was easily managed by nurses. Low incidence of complications was observed: 2 thrombosis episodes, 3 skin infection with 2 septicemiae, 1 air embolism, 1 anaphylactoid reaction. No death was related to the technique itself. IJVC offers a new method of percutaneous central vein cannulation, providing a safe and reliable temporary vascular access immediately usable for all kinds of extracorporeal treatment.

Adult↗