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Xavier Roblin

Publications and source records attributed to Xavier Roblin.

13 recordsLinked to original sources
PubMed2007

Multidrug resistance gene-1 polymorphisms and resistance to cyclosporine A in patients with steroid resistant ulcerative colitis.

BACKGROUND: Cyclosporine A (CsA) is inconstantly effective in inducing remission in acute attacks of ulcerative colitis (UC) not responding to steroids. This study aimed to establish whether multidrug resistance gene (MDR)1 polymorphisms would be associated with CsA failure. PATIENTS AND METHODS: The distribution of the different genotypes of single nucleotide polymorphisms (SNP) G2677T/A and C3435T of MDR1 exons 21 and 26, respectively, was studied in 154 patients (mean age, 44 yr) who had received CsA to treat severe attacks of steroid resistant UC in 11 centers in France and Belgium. Patients were classified as CsA failure (n = 50) when they needed colectomy within 30 days after CsA initiation. The SNPs were detected by use of a 5' nuclease allelic discrimination assay. RESULTS: There was a significant association between the G2677T/A polymorphism distribution (exon 21) and the risk for CsA failure (P = 0.0001). The TT genotype of exon 21 was significantly associated with the risk compared with the two other genotypes (odds ratio, 3.77; 95% confidence interval, 1.42-9.97, P = 0.007). There was no significant association between the genotype C3435T distribution (exon 26) and the risk of CsA failure (P = 0.23). CONCLUSION: The TT genotype of exon 21 MDR1 polymorphisms is associated with a higher risk of CsA failure in patients with steroid resistant UC. Further studies should be performed to establish whether other treatments could be more efficient to avoid surgery in this subset of patients.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2003

[Correction of insulin resistance syndrome does not cause normalisation of hyperferritinaemia].

UNLABELLED: The consequences of iron overload from dysmetabolic hyper-ferritinaemia are a strong motivation for an active medical care program. Venesection therapy is known to be effective in controlling iron overload parameters although no study has evaluated the impact of the normalization of metabolic dysfunction on iron overload. AIMS: To evaluate the impact of normalization of metabolic dysfunction on iron overload. METHODS: Sixty consecutive patients with dysmetabolic hepatosiderosis were included in a prospective study. Patients with hyper-ferritinaemia above 1000 microg/l were excluded. Multidisciplinary care was offered to all patients to normalize metabolic disorders (body mass index, arterial hypertension, fasting and postprandial hyperglycemia, hyperuricemia, hypercholesterolemia and hypertriglyceridemia) every three months. All patients were followed for one year. At clinical examinations, ferritinaemia concentrations were measured and all dysmetabolic parameters evaluated. MRI was performed at the beginning of the study and at the one year follow-up, to measure hepatic iron load. RESULTS: Despite efficient medical care of insulin resistance syndrome, ferritinaemia remained stable. In two thirds of the study population, hyper-ferritinaemia reached at least one and a half times the baseline value, although the dysmetabolic disorders of 40% of the patients were strictly normalized. In this group of 44 patients with strict normalization of metabolic functions, 24 (54%) had hyper-ferritinaemia at one year follow-up whereas 16 other (36%) normalized this parameter. Only 4 patients who had a ferritinaemia below 450 microg/l at baseline, normalized this value at one year. Intra-hepatic iron overload, evaluated by MRI imaging remained stable except for 2 patients who normalized ferritinaemia. CONCLUSION: Although efficient handling of dysmetabolic disorders is essential, it is not sufficient to normalize dysmetabolic hyper-ferritinaemia. Only patients with a ferritinaemia value below a baseline of 450 microg/l had normalization of iron overload. Therefore venesection must be offered to all patients with a hyper-ferritinaemia above this value.

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