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A Nivelon-Chevallier

Publications and source records attributed to A Nivelon-Chevallier.

At least 37 records · Page 2Linked to original sources

[An example of detection of heterozygotes and antenatal diagnosis in four families with anhidrotic ectodermal dysplasia].

Anhidrotic ectodermal dysplasia is an X-linked inherited skin disorder; only affected males exhibit the complete syndrome, whereas females may have a few mild features. The gene involved in this disease is located in the proximal area of the long arm of the X chromosome, in the q13 position. Molecular analysis is very helpful for calculating the risk of transmission in sisters with normal phenotypes and affected individuals (family 1 provides an example), but cannot solve all problems (example of family 4). The best results are obtained when there are two informative markers, each located on either side of and very close to the mutant gene. Molecular analysis can also be applied to chorionic villi sampled at the tenth week of gestation in order to achieve antenatal diagnosis in male fetuses in high risk families. Until recently, antenatal diagnosis could be performed only at the twentieth week of gestation by the demonstration of inadequate development of skin glands in skin biopsy specimens sampled under fetoscopy. Family 2 provides an example of antenatal diagnosis and highlights the risk of error that always exists in molecular analysis studies.

Ectodermal Dysplasia↗

Coffin-Lowry syndrome: a multicenter study.

The Coffin-Lowry syndrome is an inherited syndrome of mental retardation, characteristic facies and skeletal anomalies. The occurrence of severe manifestations in males, with no instance of male-to-male transmission, suggests an X-linked inheritance. The paper describes seven families from five European Centers.

Adult↗

[X maternal mosaicism and genetic counseling].

Among number of women having consulted for repeated miscarriages about sixty have a gonosomic mosaicism involving chromosome X for which abnormal clones (monosomy and/or excess) are always the minority. A retrospective study of the obstetrical follow up these patients have shown that 23% of them will give birth to a child with a chromosomic abnormality (21 trisomy, 13 trisomy, 45,X, 45,X/46,X iso X (q), 48,XXXX, 49 XXXXXY, del 5 p-). The hypothesis of a tendency toward non-disjunction is pushing for an prenatal diagnosis for patients with X mosaicism. However one can question about the real meaning of this abnormality regarding to the fact that the patients referred are not representative of the general population. Should interchromosomic interaction be taken for responsible? Is the risk for having a child chromosomic abnormality, especially X aneuploidy the same than for the overall population. It certainly would be rewarding to look after these different hypothesis in a multicentric collaborative study.

Abortion, Habitual↗

[Translocation (X; Y) and genetic counseling].

A t(X; Y) was discovered in 32 year-old female patient who has had three consecutive miscarriages. Molecular analysis of the loci DXS 31 and DYS 22 was performed which confirmed and precise the breakpoints at Xp22.3 and Yq11. Genetic counselling was based upon the accurate definition of the chromosome rearrangement and the analysis of the outcomes of similar published observations.

Abortion, Habitual↗

[Treatment of citrullinemia. Apropos of a case followed from birth. Importance of alpha-ketonic acids].

From day 1 to day 3, the protein intake of this neonate was restricted to 1 g/kg/d. It included a) essential amino acids (i.e. histidine, lysine, threonine, tryptophan), b) arginine (1,000 mg/d), c) alphaketoisovaleric 500 mg/d, alpha-ketoisocaproic (500 mg/d), alphaketobetamethylvaleric (500 mg/d), alphaketogammamethylthiobutyric (200 mg/d), betaphenylpyruvic (400 mg/d) acids. 250 mg/kg/d of sodium benzoate were given. Caloric and water intakes were 120 cal/kg/d and 120 ml/kg/d respectively. Afterwards, this procedure was modified according to clinical and biological data including serum ammonia and amino acid levels. Alpha-ketonic acid absorption and metabolism were studied on day 29. Both were fast. The detection of alloisoleucine, which is not metabolized was the consequence of the use of alphaketobetamethylvaleric acid. Until the age of 21 months, clinical and metabolic status was satisfactory. At this time, repeated seizures without metabolic failure were accompanied by psychomotor damages.

Amino Acid Metabolism, Inborn Errors↗

[Second prenatal diagnosis in a familial form of male pseudohermaphroditism caused by 17 keto-reductase deficiency: prediction confirmed by a normal third male infant].

In the first child of this family, the diagnosis of male pseudo-hermaphroditism due to 17 keto-reductase deficiency was established at two months of age after HCG test. During the second pregnancy, amniocentesis was performed for fetal karyotype and steroid determination in the amniotic fluid: an affected male fetus was suspected and this prediction was confirmed at birth. For the third pregnancy, a prenatal diagnosis was requested again and made, according to the same procedure: a normal male fetus was predicted and this diagnosis was confirmed at birth; this study demonstrates the feasibility and reliability of a prenatal diagnosis for 17 keto-reductase deficiency.

17-Hydroxysteroid Dehydrogenases↗

[An XX male newborn infant. A genetic and endocrinologic study].

The second child of a non consanguineous couple had a male phenotype with two intrascrotal testes of normal size however a scrotum bifidum was noted. The karyotype of the child was 46 XX and the parents one's was normal. No Y specific sequence was detected by using four Y specific probes (47 B, 12 F3, 52 D and 118). During the first semester of life, hormonal investigations showed a normal testicular function.

Androgens↗

[Prenatal diagnosis in a familial form of male pseudohermaphroditism due to 17-keto reductase deficiency].

In an infant considered at birth as a female but with easily palpable gonads in the labia major, the XY karyotype and the endocrine studies (determination of plasma levels of steroid hormones under basal conditions and during hCG stimulation) were consistent with the diagnosis of male pseudohermaphroditism due to 17-keto reductase deficiency. During the second pregnancy an amniocentesis revealed a 46 XY karyotype. Endocrine studies performed on the amniotic fluid at midgestation suggested that the fetus was affected by the same enzyme defect. After birth, the diagnosis was demonstrated with anatomical an endocrine studies.

17-Hydroxysteroid Dehydrogenases↗

[Trisomy 18 and prune belly syndrome].

Ultrasonic examination in a thirty five years old woman about to undergo midtrimester amniocentesis suggested an intra abdominal fetal mass. The mass was a grossly distended urinary bladder. The pregnancy was terminated at 20 weeks. Necropsy was confirmative for a prune-belly syndrome. Chromosomal analysis demonstrated a 47 XY + 18 karyotype.

Adult↗

[Homogeneous triploidy in 2 premature infants (69 XXY)].

Two new cases of 69 XXY triploidy in live-born neonates are reported. As in 40 others cases of literature observed after 24 weeks of gestation, this chromosome abnormality was lethal. The clinical features are: a large posterior fontanelle, low set ears, syndactylies of hands and feet, and genital abnormalities in the presence of a 69 XXY karyotype. The first patient present a macrocytosis of red blood cells. Macrocytosis, large polymorphonuclear leukocytes and platelets can evoke the diagnosis of triploidy in a malformed newborn.

Chromosome Aberrations↗

[Gonad function of women with homogenous karyotype XO or with mosaic form. Five case histories of fertile women (author's transl)].

The authors report five cases of fertile women who have Karyotype XO. After a short review of the classification of Turner's syndrome and of the physiopathology of the defective gonads in these patients, 79 cases in the literature and these 5 cases were reviewed and they allow us: a precise description of the morphology of these patients, which is dominated by the high incidence of small growth and the presence of the various degrees of malformations often found in Turner's syndrome; to study the gonad structure and function of these patients who have spontaneous menstruation. And finally to analyse the prognosis of pregnancies that have occurred in 33 women with an XO clone. These women have not only a raised incidence of spontaneous abortions at 32% but also frequent fetal malformations and chromosome abnormalities in the products of conception. It is therefore vital to carry out early amniocentesis in these patients.

Abnormalities, Multiple↗