Biomedical subjects
Publications and source records attributed to A Lemoine.
The goal of this article is to describe a rational step-wise strategy for using standard laboratory tests to obtain diagnostic orientation for a liver disorder; establish, support, or rule out a liver disorder; and monitor the course of treated and untreated patients with liver disorders.
Lymphoproliferative disorders (LPDs) are a serious side effect of immunosuppression after liver transplantation, and the introduction on the market of a new immunosuppressive drug has been associated with an increased risk of these disorders. To compare the effect of cyclosporine A (CSA) and FK506 in a clinical setting, the incidence of monoclonal or oligoclonal gammopathies known to often precede the appearance of LPDs was evaluated. A total of 88 adult patients was analyzed, 46 were prospectively randomized to CSA and 42 to FK506 for immunosuppression. None of these patients had gammopathy before transplantation. All the patients were tested for immunoglobulin abnormalities five to nine times during a period of 1 year and then two to four times per year thereafter from December 1990 until March 1997. The same incidence of serum immunoglobulin (Ig) abnormalities was observed in both groups (13%) with a mean delay of appearance of 11.1 +/- 5.9 versus 7.6 +/- 3.6 months for CSA and FK506, respectively (P > .05). In each group, the gammopathies were transient in 3 patients and persisted in 2. The class of Ig involved was IgG, and a monoclonal component was documented in 2 patients treated with CSA and in 3 patients with FK506. One patient treated with FK506 developed an LPD localized to the lymph nodes 8 months after the occurrence of serum protein abnormalities. The lymphoproliferative lesions subsequently disappeared with the reduction of immunosuppression. In this study, an immunosuppressive regimen of FK506 has not shown an increased incidence of lymphoproliferation compared with CSA in adult liver transplant patients.
BACKGROUND: Hepatitis C virus infection (HCV) is associated with a variety of extrahepatic disorders such as membranoproliferative glomerulonephritis (MPGN), which is generally due to cryoglobulinemia. After liver transplantation for HCV cirrhosis, alpha-interferon treatment against the recurrence of HCV in the liver graft is poorly effective and may induce intractable graft rejection. METHODS: We describe the cases of four liver transplant recipients treated with ribavirin for HCV-related glomerulopathy and nephrotic syndrome. RESULTS: The nephrotic syndrome was attenuated or disappeared during ribavirin therapy, and patients showed a marked decrease in proteinuria and an increase in albuminemia. The syndrome relapsed in two patients when ribavirin therapy was stopped, and a favorable response was again obtained in both cases when the treatment was resumed. The main adverse effect of ribavirin was anemia in two patients with renal impairment. No graft rejection occurred. CONCLUSIONS: These findings suggest that continuous therapy with low doses of oral ribavirin may improve the proteinuria of hepatitis C-related glomerulonephritis, at least in liver transplant recipients.
Azathioprine-induced veno-occlusive disease of the liver mainly described after kidney transplantation is as rare as severe with a high mortality due to acute portal hypertension and liver failure. A kidney-transplanted patient with severe azathioprine-induced veno-occlusive disease of the liver and worsening despite drug discontinuation was treated by emergency transjugular intrahepatic portosystemic shunt. Whereas the veno-occlusive disease was controlled, the patient developed severe intractable portosystemic encephalopathy successfully treated by a stent reducer maintaining a certain degree of portal diversion. Twelve months after transjugular intrahepatic portosystemic shunt, liver function was normalized and the stent was thrombosed with a subnormal liver histology. Thirty-six months after transjugular intrahepatic portosystemic shunt the patient is alive with normal liver function tests and kidney graft function. Transjugular intrahepatic portosystemic shunt for treatment of severe veno-occlusive disease of the liver is an alternative to tide the patient over until recovery of liver function.
Cyclosporine toxicity is still a significant problem in the early period after liver transplantation. The monoethylglycinexylidide (MEGX) test performed in the donor has been suggested as a reliable test to predict liver graft function in the recipient. The MEGX test was performed in 50 consecutive donors, and the clinical course of recipients, metabolic parameters of the grafts, and cyclosporine levels were followed in detail for 10 days. Two patients died of sepsis and were excluded. Renal and/or neurological toxicity appeared in 15 of the remaining 48 patients (31%). In the 6 with neurological problems, MEGX values were low (41, 47, 50, 60, 94, and 101 micrograms/L). Nine patients had transient elevations of creatinine and urea; in 8 of these, cyclosporine levels remained in the normal range. Low MEGX values in the donors correlated with early evidence of cyclosporine toxicity (P < .0001), reduced graft function (bile output, P = .04; prothrombin time at day 5, P = .005), and prolonged stay in the intensive care (P = .022). The MEGX test is valuable and reflects the metabolic capacity of liver grafts. It can predict posttransplantation complications caused by cyclosporine toxicity, and further study would evaluate its incorporation into immunosuppressive protocols.
BACKGROUND: A small animal model of one-stage total hepatectomy is needed for the study of the consequences of fulminant liver failure and to investigate the extrahepatic metabolism of drugs metabolized by the liver. The models of hepatectomy described previously in the rat have the disadvantage of multiple stages, technical difficulty, or achievement of only an incomplete removal of the liver tissue. METHODS: A Y-shaped graft was prepared from the inferior vena cava and the left renal vein of a donor rat. A total hepatectomy was performed in a recipient rat. The graft was placed and the portorenal and lower cavocaval anastomoses were performed by means of the polyethylene cuff technique. The upper cavocaval anastomosis was fashioned with a continuous suture. The procedure was performed on 49 rats, and the animals were studied for survival and biochemical profiles. RESULTS: The surgical procedure took a mean of 40 +/- 5 minutes and was not associated with any operative deaths. The portal clamping time did not exceed 15 minutes. Spontaneous mean survival of the anhepatic rats was 360 +/- 30 minutes, and glucose supplemented animals had a mean survival time of 20 +/- 5 hours. The anhepatic state was associated with significant metabolic and biochemical alterations. CONCLUSIONS: This procedure is quick to perform and does not require considerable microsurgical expertise. It provides a reproducible small animal model of total hepatectomy that is particularly useful for metabolic studies.
OBJECTIVE: The objective of this study was to analyze the specificity of detecting liver tumor cell dissemination by alpha-fetoprotein (AFP) mRNA in peripheral blood. SUMMARY BACKGROUND DATA: Alpha-fetoprotein mRNA has been used for the detection of circulating micrometastatic tumor foci of hepatocellular carcinoma (HCC); however, the interpretation of the results has been equivocal. METHODS: Sixty-four consecutive patients with malignant HCC (n = 20), liver metastases (n = 27), or nonmalignant (n = 17) liver diseases undergoing partial or total hepatectomy and orthotopic liver transplantation were included in this prospective study from January to July 1995. Peripheral blood samples were obtained before surgery, during surgery, and after surgery (range, 6-15 months). Total mRNA was extracted from nucleated cells, and cDNA synthesis and polymerase chain reaction amplification (nested polymerase chain reaction in one tube) were performed with specific AFP primers. RESULTS: Preoperative AFP mRNA was detected in 20 patients (17%), of which 5 of 20 had HCC. Intraoperative assessment showed positive AFP mRNA values in a total of 34 patients (53%) with various causes, of which 8 of 20 (40%) had HCC, 17 of 27 (63%) had other malignancies, and 9 of 17 (53%) had nonmalignant diseases. Recurrent tumor in patients with HCC occurred in four cases after surgery (range, 6-15 months) and did not correlate with AFP mRNA positivity before surgery, during surgery, or after surgery. CONCLUSIONS: Alpha-fetoprotein mRNA in peripheral blood is not a specific marker of circulating micrometastases from HCC, especially in the context of surgical treatment of HCC.
The molecular basis of cirrhosis, the most frequent underlying liver disease in hepatocellular carcinoma, remains unclear. We investigated microsatellite instability at six different loci on chromosomes 2p, 3p, 5q, 9p, 13q and 17p, in DNA from 38 cirrhotic livers of viral (n=28) and nonviral (n=10) origin. Sixty percent of the patients exhibited microsatellite alterations in at least one chromosome locus. A striking feature was the close association between genomic instability and cirrhosis linked to hepatitis B viral infection (P<0.01). This high instability may be a clue to the etiology of cancer induced by the hepatitis B virus.
A cDNA clone encoding a larval-pupal cuticular protein, named TMLPCP-22, has been isolated by screening a library in expression vector with a monoclonal antibody made against pupal cuticular proteins of Tenebrio molitor. Northern-blot and in situ hybridization analyses showed that the expression of TMLPCP-22 is regulated in a stage-specific and tissue-specific manner; the transcript was present during the secretion of preecdysial larval and pupal cuticles and was restricted to epidermal cells. No expression was observed during adult cuticle deposition. In supernumerary pupae obtained after application of a juvenile hormone analogue, which is known to inhibit the adult programme, TMLPCP-22 mRNA was expressed again, confirming its larval-pupal specificity.
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The effects of administration of endotoxin to donors or recipients on the mortality rate, evolution of endotoxin levels, and tumor necrosis factor alpha (TNF-alpha) release were investigated in a syngenic orthotopic liver transplantation model in Lewis rats with portal reperfusion only. No significant recipient endotoxemia, TNF-alpha release, or mortality occurred in control recipients following transplantation from normal donors. The doses of endotoxin needed to kill 50% and 100% of animals after hepatic artery ligation were, respectively, 4 mg/kg and 10 mg/kg. Transplantation of animals' livers with no preservation phase from donors who were administered a lethal dose of endotoxin for this combination (10 mg/kg) produced significant recipient endotoxemia at 10 min (6.9 +/- 2.5 x 10(3) endotoxin unit/ml (EU/ml), P < 0.01), 45 min (8.8 +/- 1.1 x 10(3) EU/ml, P < 0.001) and 8 hr (18.5 +/- 3.5 x 10(3) EU/ml, P < 0.001) after graft reperfusion. Significant levels of TNF-alpha were also detected in these animals at 45 min (280 +/- 70 pg/ml, P < 0.007) and 8 hr (80 +/- 40 pg/ml, P < 0.05) when compared with the controls. Mortalities in recipients of OLT from donor animals that had received endotoxin (2 mg/kg or 4 mg/kg) immediately prior to the harvesting procedure was 0% and 20%, respectively, compared with no death in the control group. When recipient animals were administered endotoxin immediately after graft reperfusion the resistance to endotoxin administration was significantly reduced compared with animals that had not received OLT (LD50 < 2 mg/kg versus 4 mg/kg; LD100 4 mg/kg versus 10 mg/kg, respectively). These results show that endotoxin and its effects can be transferred from the liver graft donor to the recipient and that OLT per se reduces the recipient resistance to endotoxin with subsequent increase in mortality.
We report an original application of competitive reverse transcription-polymerase chain reaction (RT-PCR) for the quantification of MDR1 mRNA in clinical specimens by simultaneous reverse transcription and PCR amplification of cellular RNA with decreasing amounts of an internal standard. The competitor RNA shares the same MDR1 primer sequences as the cellular mRNA, but yields a different-sized PCR product. This allows resolution of the amplified cDNA fragments after agarose gel electrophoresis and ethidium bromide staining. The concentration of MDR1 mRNA is derived from the ratio between the intensities of the bands corresponding to the amplified products. We have used this assay to measure MDR1 expression in breast carcinomas and assessed the precision, sensitivity, and accuracy of the method. Competitive RT-PCR is a simple, highly specific, nonradioactive procedure for the quantification of MDR1 mRNA and is particularly suitable for use in the clinical laboratory.
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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.
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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.
We performed a double blind randomized study in order to assess the efficacy of a multivitamin supplement for the prevention of common infections in healthy elderly subjects. Non-institutionalized, independent subjects over 60 years of age, living in the Nevers area (central France) were recruited by announcements and randomly assigned to a treatment or a placebo group. The treatment or placebo tablets were to be taken daily for 4 months. The principal criterion of response was the incidence of infections, as recorded from a detailed questionnaire presented at entrance, in the middle (2 months) and at the end (4 months) of the study. Blood samples were taken at the entrance in the study and after two and four months in order to monitor vitamin status. No significant difference was found between the two groups for the incidence of infections. In fact the observed incidences during the two two-month periods were higher in the treatment (0.38 and 0.21) than in the placebo group (0.29 and 0.13). After two months and after four months of supplementation, blood vitamin indicators of the subjects were significantly higher in the treatment than in the placebo group for vitamins B1, B2, B6, E and folates (p < 0.001). The improvement of the vitamin C status was slightly higher in the treatment than in the placebo group. For vitamin A status, the evolution was similar in the two groups. In conclusion, short-term supplementation of healthy elderly subjects with the investigated supplement is not likely to afford a meaningful protection against common infections.
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