PubMed Health⌕ Search

Biomedical subjects

M Prieur

Publications and source records attributed to M Prieur.

At least 109 records · Page 6Linked to original sources

[Oral contraceptives and trisomy 21. A retrospective study of 730 cases (author's transl)].

A retrospective study of 730 cases of trisomy 21 and of 1 035 cases of abnormal children without a detectable chromosomal aberration, allows the study of the frequency of use of oral contraceptives by their mothers. The statistical analysis shows no notable differences for mothers 30 years old and younger. Among the mothers 30 to 38 years old, these is an excess of pill-taking by mothers of trisomy 21 children. For this second category of mothers (30 to 38 years) this excess is significant (a) when the delay between the cessation of pill-taking and the conception of the child is six months of less; (b) when the duration of pill-taking has been longer than one year; and (c), when those two factors are present simultaneously. Moreover, the frequency of males is significantly reduced in trisomy 21 children when their mothers have taken the pill. As a whole, for the subsample of mothers 30 and older, a correlation is observed between the three factors analysed, pill-taking, sex ratio, and trisomy 21. In view of the fact that decrease of the sex ratio and the increase of the frequency of trisomy 21 both are correlated with maternal aging in the general population, it seems remarkable that a correlation between these two variables and the use of oral contraceptives is observed only when the women had already passed the first of their reproduction period.

Adolescent↗

[A jumping translocation (5p;15q), (8q;15q), and (12q;15q) (author's transl)].

Three balanced karyotypes (5p;15q), (8q;15q), and (12q;15q) were found simultaneously in a child with the Willi-Prader syndrome. The hypothesis is presented of a "jumping# translocation by affinity of telomeric and interstitial palindromes. The relationship between the Willi-Prader syndrome and a juxtacentric anomaly of the long arm of chromosome 15 is discussed.

Child, Preschool↗

Systematic analysis of 95 reciprocal translocations of autosomes.

The statistical analysis of 95 cases of reciprocal translocations involving autosomes detected among about 10,000 patients studied with the R-banding technique gives the following information: 1. An excess of break points exists for chromosome arms 4p,9p, 10q, 21q, and 22q and a deficiency for 1p, 2p, and 6q. Furthermore, there are relatively more break points in the small arms than in the large arms, when the translocation is ascertained through an unbalanced translocation carrier. Except for chromosome 22, an ascertainment bias explain this non random distribution. 2. An excess of telomeric break points exists in all cases of translocations ascertained through unbalanced carriers, and an excess of centromeric break point exists in the case of 3:1 and 1:3 segregations only. These excesses are also explained by an ascertainment bias. 3. The break points are located usually at the junction of the bands (interfaces). 4. The size of the chromosomal imbalance varies in the ascertainment classes. It is very large in cases ascertained through balanced carriers (at least one break point is far from the telomere), large in cases ascertained through abortion, and relatively moderate in cases ascertained through unbalanced translocation carriers (at least one break point is juxta telomeric). 5. An excess of balanced reciprocal translocations exists in our sample of mentally retarded and malformed children (position effect?). 6. An excess of balanced reciprocal translocations (not involving chromosome 21) exists among the trisomics 21 and their parents (interchromosomal effect?). 7. A large excess of maternal transmission exists in cases of 3:1 segregation of reciprocal translocation.

Abnormalities, Multiple↗

[Possible localization of the glutathione reductase (EC 1.6.4.2) on the 8p21 band].

Glutathione reductase (EC 1.6.4.2.) (GSR) activity was measured in the red cells of patients with different rearrangements of chromosome 8. Of three patients with mosaic trisomy 8, two had a high GSR activity. The lack of correlation between GSR levels and the degree of mosaicism in lymphocytes is discussed. In six patients with trisomy 8qter the mean value of GSR activities was normal. In one patient with trisomy pter leads to q22.1 and in two with trisomy p11 leads to p22, a significant increase (+60%) of GSR activity was observed. In two patients with monosomy p22 leads to pter and p21 leads to pter, respectively, the GSR levels were normal. It is concluded that the gene locus of GSR can be assigned to the 8p11 leads to p22 segment. A comparison of these results with one other case from the literature suggests a more precise assignment of the GSR locus to band p21.

Chromosome Mapping↗

[Chromosome 8 : complete trisomy and segmental trisomies].

The phenotypic effects of trisomy of various segments of chromosome 8 have been recognized through the analysis of twelve different patients: five mosaic cases of trisomy 8, one case of trisomy for the short arm and the proximal segment of the long arm, two cases of trisomy for a portion of the short arm, and four cases of trisomy for the terminal segment of the long arm. Analysis of the data from the literature and of these personal observations allows the definition of three syndromes: trisomy 8, trisomy 8p and 8q proximal, and trisomy 8q terminal. Three clinical signs are common to the three syndromes: vertebral anomalies, depression of the mesosternum, and bulging of the forehead. This suggests that different segments of chromosome 8 carry genes affecting osseous growth. Trisomy 8p causes, in addition to severe mental deficiency, a thick nose, a large mouth, and microcephaly. Other clinical signs can be assigned to three groups corresponding to the short arm, the proximal part, and the distal part of the long arm.

Abnormalities, Multiple↗