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D Azoulay

Publications and source records attributed to D Azoulay.

At least 73 records · Page 4Linked to original sources
PubMed1995

What should I do about my patient's gall stones?

The problem of benign biliary disease is one that causes significant morbidity and social economic strain in the western world. The classical treatment, cholecystectomy, has been challenged by various medical and surgical techniques in a seemingly random nature. The development of the treatment of gall stone disease is reviewed by analysis of published studies over the last 20 years. The advantages and disadvantages are discussed as an overview and summary of the current management of gall stone disease in the light of our knowledge of its malignant potential.

Chenodeoxycholic Acid↗
PubMed1994

FK 506 renal toxicity and lack of detectable cytochrome P-450 3A in the liver graft of a patient undergoing liver transplantation.

Many commonly used drugs are substrates for hepatic cytochrome P-450 3A in human beings, and its role in the metabolism of potentially toxic immunosuppressants has been highlighted (cyclosporine, FK 506). One hundred fifty human liver grafts were biopsied before and after liver transplantation, and levels of cytochromes P-450 3A, 1A2, 2D6 and 2C were estimated by means of the Western-blot technique and correlated with histological appearance, glycogen content and clinical course. In 15 of the grafts, cyclosporine oxidase was also measured, and in 12 of 15 recipients, urinary 6 beta-hydroxycortisol excretion was assayed. A wide range of cytochrome P-450 3A values were observed (25 to 366 arbitrary units/mg; mean, 105 +/- 63 arbitrary units/mg). In one graft (no. 730) no cytochrome P-450 3A was detectable on immunoblotting, despite increasing homogenate concentrations. In this sample, cytochromes P-450 1A2, 2D6, and 2C were present in normal ranges. Levels of cyclosporine oxidase and 6 beta-hydroxycortisol in the urine specimens of the recipient were found to be low. The recipient of graft 730 experienced reversible complications of FK 506 therapy despite adherence to the administration protocol and drug plasma level in the normal range. The subsequent appearance of the cytochrome P-450 3A was associated with the consequent tolerance of oral FK 506. The absence of detectable amounts of P-450 3A in one biopsy from a donated human liver graft dramatically emphasizes the extreme range of this enzyme levels and has important clinical implications.

Adolescent↗
PubMed1994

Transjugular intrahepatic portosystemic shunt worsens the hyperdynamic circulatory state of the cirrhotic patient: preliminary report of a prospective study.

The aim of this prospective nonrandomized study was to assess the immediate and short-term sequelae of transjugular intrahepatic portosystemic shunting on the circulatory hyperdynamic state of the cirrhotic patient. Twelve transjugular portosystemic shunting procedures were performed in 12 cirrhotic patients for sclerotherapy failure (10 cases) and/or intractable ascites (4 cases). Self-expandable stents 10 mm in diameter were used in all cases. Portal pressure measurement and right-heart catheterization were performed before and 30 min and 1 mo after the procedure. The portoatrial pressure gradient decreased from 15 +/- 3 to 7 +/- 3 mm Hg 30 min after surgery (p < 0.0001) to 8 +/- 3 mm Hg 1 mo after surgery (p < 0.001, in comparison with basal values). The cardiac index increased from 4.5 +/- 1.3 to 5.7 +/- 1.5 L/min.m2 30 min after surgery (p < 0.001) to 7.4 +/- 1.4 L/min.m2 1 mo after surgery (p < 0.001). Systemic vascular resistance decreased from 808 +/- 323 to 646 +/- 209 dyne.sec.cm-5 30 min after surgery (p < 0.01) to 467 +/- 101 dyne.sec.cm-5 1 mo after surgery (p < 0.05). This study demonstrates that transjugular portosystemic shunting rapidly and significantly worsens the hyperdynamic circulatory state of the cirrhotic patient. Although apparently noninvasive, this procedure should be considered with caution in cirrhotic patients with limited cardiac reserve.

Adult↗
PubMed1993

Relationship between graft cytochrome P-450 3A content and early morbidity after liver transplantation.

Cytochrome P-450 3A metabolizes CsA into several metabolites with very limited pharmacological activity and toxicity. In 40 liver donors, the relative concentrations of P-450 3A was assessed by immunoblot analysis using a specific monoclonal antibody exhibited a 10-fold variation (mean = 92 +/- 50 arbitrary units [AU]/mg) in levels. Problems consequent upon CsA usage (nephrotoxicity, neurotoxicity, and hypertension) occurred in 8 of 34 transplant recipients in the immediate postoperative period, and in these 8 patients the problems were always associated with low graft P-4503A levels (mean = 52 +/- 19 A.U./mg, P = 0.0003, cf. patients with no toxicity). Four of these patients had CsA levels that were also high, but 4 had CsA levels in the therapeutic range. Episodes of early graft rejection were related to higher P-450 3A levels (mean = 110 +/- 24 A.U./mg). Cytochrome P-450 3A levels were also found to be inversely related to CsA whole blood levels (assessed with a specific antibody 12 hr after the intravenous infusion of CsA at 1 mg/kg in the recipients (P < 0.02). Cytochrome P-450 3A can provide information that should allow individualized immunosuppression with CsA maintaining therapeutic levels but avoiding toxicity in susceptible individuals.

Adult↗
PubMed1993

A minimally invasive approach to the treatment of stenosis of the portal vein after hepatic transplantation.

An original technique balloon dilatation through an ileal vein for treatment of portal vein stenosis after HT is described. In four of five patients, this minimally invasive procedure permitted avoidance of extensive dissection of the hepatic pedicle. This technique should be the treatment of choice, or at least in the first step, for portal vein stenosis after HT.

Anastomosis, Surgical↗
PubMed1993

Major pathway of imipramine metabolism is catalyzed by cytochromes P-450 1A2 and P-450 3A4 in human liver.

The metabolism of imipramine by human liver microsomes was examined using a combination of five strategies. Human hepatic microsomes produced N-desmethylimipramine (84%), 2-hydroxyimipramine (10%), and 10-hydroxyimipramine (6%). Preincubation of human hepatocytes in culture with beta-naphthoflavone and macrolides exclusively induced the formation of desmethylimpramine (552%, p < 0.05, and 234%, p < 0.003, respectively). Correlations were obtained between rates of imipramine demethylation and cytochrome P-450 (P-450) 1A2 (r = 0.88, p < 0.001) and P-450 3A (r = 0.80, p < 0.02) concentrations in human liver microsomal preparations from 13 different subjects. Anti-P-450 1A2 and anti-P-450 3A antibodies selectively inhibited N-demethylation (80% and 60%, respectively). N-Demethylation was completely inhibited when anti-1A2 and anti-3A were added simultaneously. Kinetic studies with human microsomes confirm the contribution of two different enzymes in the N-demethylation. The Km of 1A2 was similar to the high affinity Km in human liver microsomes, whereas the Km of 3A was similar to the low affinity Km in human liver microsomes. P-450 1A2 was apparently more efficient than 3A4 (lower Km and higher Vmax) but was expressed in much lower concentration. Human P-450s 1A2 and 3A4 expressed in yeast efficiently produced desmethylimipramine. These results suggest that P-450 1A2 and P-450 3A4 are the major enzymes involved in imipramine N-demethylation in human hepatic microsomes. Similar experiments were conducted using P-450 2D6, and they confirmed that P-450 2D6 catalyzes imipramine 2-hydroxylation. Interindividual variations in 3A4 hepatic content may explain the large variations in imipramine blood levels observed after uniform dosages and thus may explain the variations in clinical efficacy. Caution might be advised in the clinical use of tricyclic antidepressants when drugs are also administered that induce or inhibit P-450s 3A4 and 1A2.

Adult↗
PubMed1993

Incidence of adverse reactions to cyclosporine after liver transplantation is predicted by the first blood level.

Despite the availability of whole-blood cyclosporine assays, the different responses of individual patients to its administration after transplantation continue to pose clinical problems, particularly with respect to toxicity. Fifty-seven recipients of first orthotopic liver transplants were studied between January 1992 and July 1992. Initial immunosuppression was carried out with azathioprine, methylprednisolone and cyclosporine, at a dose of 1 mg/kg/day adjusted to achieve blood levels between 400 and 600 ng/ml. Cyclosporine levels were measured 12 hr after the start of intravenous administration and correlated with the occurrence of toxic complications. Twelve patients experienced toxic complications in the first 7 days after orthotopic liver transplantation. These were neurological in six patients (of whom four also had kidney failure) and renal complications in the other six patients. All complications were reversed by reducing or stopping administration of cyclosporine. We noted excellent correlation between the occurrence of complications and cyclosporine whole-blood levels (p < 0.0001) despite the fact that levels did not exceed the therapeutic range. However, no correlation was observed between toxicity and cumulative dosage. In this study we were able to demonstrate that a standardized dose of cyclosporine does not prevent the occurrence of toxic side effects even when cyclosporine whole-blood levels are subsequently maintained in the therapeutic range. This highlights the importance of the first dose of cyclosporine and consequent early postoperative blood levels and indicates that these problems are unlikely to be overcome until a method of predicting individual requirements can be established in clinical practice.

Adolescent↗
PubMed1993

Recent developments in liver transplantation.

The many developments that have occurred and continue to occur have also meant that the quality of life experienced by recipients of a successful graft is excellent, with more than 85% of patients returning to normal life and work (even having children). While long-term survival still occurs more frequently in favorable groups such as children with metabolic abnormalities or biliary atresia, results are still extremely good for adults, with 3-year survival figures after transplantation for cirrhosis in the order of 75%. These figures also continue to improve, and with the skill and enthusiasm that workers in this field display they seem destined to continue unabated.

Adenosine↗