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M Dupont

Publications and source records attributed to M Dupont.

At least 19 recordsLinked to original sources
PubMed2002

Multiplex fluorescent RT-PCR to quantify leukemic fusion transcripts.

The detection of chimeric transcripts derived from aberrant chromosomal fusion events provides an exceptionally valuable toolfor the diagnosis of leukemia. We have developed a simple, inexpensive, reproducible, and automated method to quantify RT-PCR products. Our approach utilizesfluorescent PCRfor the co-ampification of the specific fusion transcript with an internal control (HPRT). We have also combined the advantages of real-time quantitative PCR, namely continuous fluorescent detection of PCR products with the low cost of an endpoint assay by examining in a novel manner the amount offluorescent PCR product generated during the exponential phase of amplification. This has been achieved by using the automated loading and quantification capacity of a laser-induced fluorescence capillary electrophoresis system, the ABI PRIsMS 310A, so that we can effectively monitor amplification during the exponential phase cheaply, reproducibly, and in a sensitive manner. We have carefully verified our new technique using five leukemia cell lines, each expressing a differentfusion transcript. Specificity and reproducibility (cy within 10%) have been examined and demonstrate the excellent precision of our technology. The high sensitivity levels of at least 10(-4) to 10(-6) obtainedfor the serial dilutions of the five cell lines validate the choice of our fluorescent PCR as a comparable method to other more complicated and expensive methods. Our results have allowed us to quantify PCR products and the amount of chimeric mRNA originating from the translocation breakpoint. We demonstrate that our novelfluorescent method is useful to detect and quantify residual leukemic cells in patients undergoing therapy.

DNA Primers↗
PubMed2001

[Insertion of intrauterine device in general practice. Which women choose the IUD, and how is the procedure done?].

INTRODUCTION: In Denmark most IUDs are inserted by general practitioners (GPs). The aim of this study was to throw light on which women choose IUD, the procedure used, and difficulties associated with insertion. MATERIAL AND METHODS: All 232 GPs in Frederiksborg County were invited to participate and 88 agreed. The GP filled in a questionnaire concerning the type of IUD, the age, parity, etc, of the woman and information about the insertion. RESULTS: Eighty-eight GPs contributed with 562 IUD insertions. IUD was mostly used by women above 25 years of age and by women who had given birth to a child. There were no differences in the insertion procedures used by the doctors. Fifty-nine per cent of the women were previous IUD users. Of the former users, 37% reported problems with the previous use of the IUD. Twenty-five per cent of the women in this study reported that they had had heavy or long-lasting menstruation before insertion. Fifty-five per cent of the women had a test for chlamydia before insertion. Twenty-three (4.1%) insertions were abandoned. 26 (4.6%) insertions were described as difficult. The highest frequency was in women using gestagen-releasing IUDs. CONCLUSION: IUD was mainly used by women, who had given birth to a child. The gestagen releasing IUD was mostly used by the elder group and by women with heavy bleedings before insertion. The procedure was very identical and the number of abandoned and difficult insertions were low and only related to the type of IUD. More female than male doctors participated. Doctors working in partnerships participated more frequently than doctors working alone.

Adult↗
PubMed2001

Hydrolysis of 4-hydroxybenzoic acid esters (parabens) and their aerobic transformation into phenol by the resistant Enterobacter cloacae strain EM.

Enterobacter cloacae strain EM was isolated from a commercial dietary mineral supplement stabilized by a mixture of methylparaben and propylparaben. It harbored a high-molecular-weight plasmid and was resistant to high concentrations of parabens. Strain EM was able to grow in liquid media containing similar amounts of parabens as found in the mineral supplement (1,700 and 180 mg of methyl and propylparaben, respectively, per liter or 11.2 and 1.0 mM) and in very high concentrations of methylparaben (3,000 mg liter(-1), or 19.7 mM). This strain was able to hydrolyze approximately 500 mg of methyl-, ethyl-, or propylparaben liter(-1) (3 mM) in less than 2 h in liquid culture, and the supernatant of a sonicated culture, after a 30-fold dilution, was able to hydrolyze 1,000 mg of methylparaben liter(-1) (6.6 mM) in 15 min. The first step of paraben degradation was the hydrolysis of the ester bond to produce 4-hydroxybenzoic acid, followed by a decarboxylation step to produce phenol under aerobic conditions. The transformation of 4-hydroxybenzoic acid into phenol was stoichiometric. The conversion of approximately 500 mg of parabens liter(-1) (3 mM) to phenol in liquid culture was completed within 5 h without significant hindrance to the growth of strain EM, while higher concentrations of parabens partially inhibited its growth.

Biodegradation, Environmental↗
PubMed2001

[Regulation of harvesting for scientific use in France].

The 94-654 law (dated 29th July 1994) has modified the french regulation on post-mortem sampling on a deceased person, performed for scientific reasons. The patient's permission has been made mandatory for every autopsy (with the exception of forensic medecine). The permission can be presumed when the autopsy is performed to find the cause of death. In all other cases, the patient's wish must have been expressly signified before death, or testified by his family. In any case, the patient's relative must be informed of the sampling. This law seems to be one reason for the very perceptible decrease of the number of autopsies performed in hospitals these last years.

Autopsy↗
PubMed2000

Development of an Escherichia coli expression system and thermostability screening assay for libraries of mutant xylanase.

A thermostability screening assay was developed using an Escherichia coli expression system to express Streptomyces lividans xylanase A (XlnA). The screening system was tested using mutants randomized at position 49 of the S. lividans XlnA gene, a position previously shown to confer thermostability with a I49P point mutation. The library was cloned into an E. coli expression vector and transformed into XL1-blue bacteria. The resulting clones were screened for increased thermostability with respect to wild-type XlnA. Using this assay, we isolated the I49P mutant previously shown to be thermostable, as well as novel I49A and I49C mutants. The I49A and I49C mutants were shown to have 2.8- to 8-fold increase in thermostability over that of wild-type XlnA. The results show that the screening assay can selectively enrich for clones with increased thermostability and is suitable for screening small- to medium-sized libraries of 5000-20,000 clones.

Journal Article↗
PubMed1999

Simple variant t(8;21) acute myeloid leukemias harbor insertions of the AML1 or ETO genes.

We report on the molecular characterization of two acute myeloid leukemias (AML), one AML-M1 (patient 1) and one AML-M2 (patient 2) with t(8;21)(p21;q22) and t(8;20)(q22;p13), respectively, at diagnosis. The locations of the breakpoints, 21q22 in patient 1 and 8q22 in patient 2, prompted us to search for a cryptic t(8;21)(q22;q22) and involvement of the AML1 and ETO genes. Dual-color fluorescence in situ hybridization (FISH) using whole chromosome painting probes for chromosomes 8, 20, and 21 confirmed the conventional cytogenetic karyotypes. However, dual-color FISH using appropriate ETO and AML1 probes disclosed an insertion of AML1 into 8q22 on the derivative chromosome 8 in patient 1 and of ETO into 21q22 on one chromosome 21 in patient 2, leading to AML1-ETO fusion signals. Both cases expressed an AML1-ETO transcript, shown by reverse transcriptase polymerase chain reaction and cDNA sequencing. Creation of functional AML1-ETO fusion genes in these two simple variant t(8;21) probably occurred through complex mechanisms, combining translocation and insertion of chromosomal segments.

Adolescent↗
PubMed1998

Phenotype-genotype correlation in Jewish patients suffering from familial Mediterranean fever (FMF).

Familial Mediterranean Fever is one of the most frequent recessive disease in non-Ashkenazi Jews. The gene responsible for the disease (MEFV) has very recently been identified. The M694V ('MED') mutation was found in about 80% of the FMF Jewish (Iraqi and North African) chromosomes. To see if the presence of this mutation could be correlated with particular traits of the disease, we examined a number of clinical features in a panel of 109 Jewish FMF patients with 0, 1 or 2 MED mutations. We showed that homozygosity for this mutation was significantly associated with a more severe form of the disease. In homozygous patients, the disease started earlier (mean age 6.4 +/- 5 vs 13.6 +/- 8.9) and both arthritis and pleuritis were twice as frequent as in patients with one or no M694V mutation. Moreover, 3/3 patients with amyloidosis displayed two MED mutations. No association was found with fever, peritonitis, response to colchicine and erysipeloid eruption. The present result strongly suggests the potential prognostic value of the presence of this mutation.

Africa, Northern↗
PubMed1998

Non-founder mutations in the MEFV gene establish this gene as the cause of familial Mediterranean fever (FMF).

Familial Mediterranean fever (FMF) is an autosomal recessive disorder characterized by recurring attacks of fever and serositis. It affects primarily North African Jews, Armenians, Turks and Arabs, in which a founder effect has been demonstrated. The marenostrin-pyrin-encoding gene has been proposed as a candidate gene for the disease ( MEFV ), on the basis of the identification of putative mutations clustered in exon 10 (M680V, M694I, M694V and V726A), each segregating with one ancestral haplotype. In a search for additional MEFV mutations in 120 apparently non-founder FMF chromosomes, we observed eight novel mutations in exon 2 (E148Q, E167D and T267I), exon 5 (F479L) and exon 10 (I692del K695R, A744S and R761H). Except for E148Q and K695R, all mutations were found in a single chromosome. Mutation E148Q was found in all ethnic groups studied and in association with a novel ancestral haplotype in non-Ashkenazi Jews (S2). Altogether, these new findings definitively establish the marenostrin/pyrin-encoding gene as the MEFV locus.

Africa, Northern↗
PubMed1998

Familial Mediterranean fever clinical and genetic features in Druzes and in Iraqi Jews: a preliminary study.

OBJECTIVE: A number of differences have been noted in clinical familial Mediterranean fever (FMF) among ethnic groups. Iraqi Jews and Druzes are characterized by less severe disease. The differences in disease expression raise the possibility of background genes peculiar to specific ethnic groups. METHODS: We analyzed a series of FMF linked microsatellite markers and searched for gene mutations in these 2 populations. RESULTS: We observed a conserved haplotype in 46% of the FMF druze chromosomes that was different from the Mediterranean haplotype but identical to the ARM3 haplotype. In contrast, 56% of the FMF chromosomes in Iraqi Jews displayed the same mutation as that found in Jews from North Africa. CONCLUSION: Variable expression in FMF is probably due to both allelic heterogeneity and/or modifier genes as well as environmental factors.

Adolescent↗
PubMed1997

Genotypic diagnosis of familial Mediterranean fever (FMF) using new microsatellite markers: example of two extensive non-Ashkenazi Jewish pedigrees.

Familial Mediterranean fever is an autosomal recessive disease characterised by multiple attacks of serosal inflammation in the absence of treatment. In the absence of timely diagnosis, renal amyloidosis is a life threatening complication. The diagnosis is often missed because no specific test is available. Early colchicine treatment prevents attacks and renal complications. The FMF gene (MEF) has been mapped to chromosome 16p 13.3 but has not yet been identified. We compared the suitability of a series of microsatellite markers (four of them were new) and propose the routine use of seven of these markers, exhibiting alleles in strong linkage disequilibrium with the disease and informative in 100% of diagnosed patients. Moreover, the discovery of a homozygous status for the 3-3-9 (or 3-3-18) haplotype at the core loci (D16S3070, D16S3082, and D16S3275), which was found in 73% non-Ashkenazi Jewish patients, points to a diagnosis of FMF, even in sporadic cases, with a risk of error of only 2.10(-5). Two extensive pedigrees covering most indications for genetic counselling are presented, showing that it is now possible both prospectively and retrospectively to identify members likely to have MEF mutations. With the help of this accurate test, colchicine treatment can be better targeted, especially where the symptomatology is mild or atypical.

Chromosome Mapping↗