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M Dousseau

Publications and source records attributed to M Dousseau.

8 recordsLinked to original sources
PubMed1998

Structural analysis of gene marker loci on chromosomes 10 and 11 in primary and secondary uraemic hyperparathyroidism.

BACKGROUND: The genetic molecular anomalies in patients with primary (I degree) and secondary (II degree) hyperparathyroidism (HPTH) are still largely unknown. In particular, the changes underlying monoclonal growth in the parathyroids of patients with II degree HPTH are not well understood. METHODS: We screened genomic DNA from a total of 30 patients with I degree HPTH and 29 patients with II degree uraemic HPTH for possible rearrangements or allelic losses of several gene markers located on chromosome 11p near the PTH gene, namely Ha-ras, IGF-2, WT1, and the PTH gene itself. In addition, two other gene markers, PRAD1 (localized on 11q13) and RET (localized on 10q11) were examined for possible structural alterations. Moreover, we used fluorescence in situ hybridization (FISH) which is another technique to detect numerical alterations of chromosome 11. RESULTS: The results show that one of 13 patients with I degree HPTH (8%) exhibited a rearrangement for the PRAD-1 gene. Loss of heterozygosity of Ha-ras locus was observed in one of 11 uraemic patients with II degree HPTH (9%). Three of 10 patients with I degree HPTH (30%) and one of 7 patients with II degree HPTH (14%) showed an allelic loss of the WT1 gene. No evidence of rearrangement or allelic loss was detected for the IGF-2, PTH or RET genes respectively. Using FISH method, three normal parathyroid gland, six I degree HPTH adenomas and eight II degree HPTH hyperplastic glands from uraemic patients were studied with centromeric probe for chromosome 11. Monosomy 11 was observed in one case of I degree HPTH and in one other case of II degree HPTH. CONCLUSION: Evidence of loss of heterozygosity for several genes located on human chromosome 11p has been found in a series of parathyroid glands from several patients with I degree and II degree uraemic HPTH, corresponding to monosomy of chromosome 11 in some cases.

Adult↗
PubMed1990

Human severe combined immunodeficiency disease: phenotypic and functional characteristics of peripheral B lymphocytes.

Human severe combined immunodeficiency disease (SCID) includes an X-chromosome-linked type characterized by a complete absence of mature T cells, hypogammaglobulinemia but normal or elevated number of B cells, suggesting that the disease results from a block in early T cell differentiation. It has been shown that B cells from obligate carrier women of this disorder exhibit the preferential use of the nonmutant X chromosome as the active X (as shown for T cells), suggesting that the SCID gene product has a direct effect on B cells as well as on T cells. To examine this question, we analyzed the phenotypic and functional characteristics of peripheral B cells from nine infants with SCID. We found a constant absence of spontaneously expressed activation Ag on B cell membrane from all SCID patients tested which contrasts with the phenotypic pattern exhibited by age-matched infants whom all cells bearing surface Ig express the 4F2 Ag and to a lesser extent the transferrin receptor. Concurrently, B cells from SCID patients have a profound impairment in their responses to stimuli that induce in vitro B cell proliferation and differentiation. Although rIL-2 and low-Mr B cell growth factor are potent inducers of proliferation on age-matched infants' B cells, they are poorly efficient in inducing proliferation of anti-mu-activated SCID B cells. This impairment is not related to the resting B cell phenotype of SCID B cells as shown by comparison with normal resting B cells. Furthermore, we observed an apparent block in B cell differentiation inasmuch as neither rIL-2 nor rIL-6 could support SAC-activated SCID B cell differentiation, both lymphokines being very efficient in inducing SAC-activated age-matched infants' B cell or purified resting B cell differentiation. These results suggest that the SCID gene defect has a direct effect on B cells and is required during B cell maturation.

Antigens, CD↗