Chromosomal prenatal diagnosis: study of 936 cases of intrauterine abnormalities after ultrasound assessment.

Nine hundred and thirty-six prenatal chromosomal analyses were performed by four cytogenetic centres after ultrasound diagnosis of fetal abnormalities, amniotic fluid disorders, fetal growth retardation, and fetal or placental abnormalities. During the same period, 6515 fetal karyotypes were analysed because of maternal age. Frequencies of chromosomal aberrations in each case were respectively 4.4, 6.7 and 15.8 per cent, compared with 3.18 per cent when the fetal karyotype was performed because of maternal age. High rates of chromosomal aberrations are observed in cases of cervical hygroma, limb abnormalities, omphaloceles, duodenal stenosis, hydrocephalus, and facial abnormalities. In the case of polymalformations, this rate was 29.2 per cent. When malformations were seen together with an amniotic fluid disorder or growth retardation, 21.5 per cent chromosomal aberrations were observed. This frequency was 10.4 per cent when growth retardation was associated with an amniotic fluid disorder. Trisomy 13, 18, 21 and monosomy X accounted for 4/5 of all abnormalities in which we observed a high rate of triploidies (4.9 per cent) and balanced (3.3 per cent) or unbalanced (9.8 per cent) non-Robertsonian structural abnormalities. Sonographic ascertainment of these aberrations and prenatal characteristics of major anomalies are discussed.

Prenatal diagnosis of a mosaic 46,XY/47,X,i(Xq)Y.

A case of mosaic 46,XY/47,X,i(Xq)Y is diagnosed at 18 gestational weeks in amniotic fluid cells and confirmed at birth in the lymphocytes of the child. The literature on Klinefelter's syndromes with structural chromosome X rearrangements is reviewed. This is the first case reported of a mosaic isochromosome Xq in a boy.

[The C cell system and experimental thyroid apudomas in the rat: the combined action of 2-acetylaminofluorene and chlorpromazine in inducing systemic medullary type tumors. An ultrastructural study]. / Le système des cellules C et les apudomes expérimentaux de la thyroïde chez le Rat: actions combinées du 2-acétylaminofluorène et de la chlorpromazine permettant l'obtention systématique de tumeurs de type médullaire. Etude ultrastructurale.

Previous chronic administration of chlorpromazine (CPZ) before the start of the 2-acetylaminofluorene (2-AAF) action and during the cancerogenic process systematically facilitate the growth of apudome-like medullary tumors inside the thyroid gland. Ultrastructural studies of normal C cells, adenomatous C cells and cancerous C cells derivated from the normal cellular type show various specific transformations of few intracytoplasmic organelles. In the Golgi apparatus, the path of main maturation of calcitonin-like granules seems the same in the normal and in the adenomatous cells. On the contrary, the amount of calcitonin-like granules falls in the tumoral extensive tissue even though the golgian activity turns towards a high abnormal proliferation of clathrin vesicles or coated vesicles. This new fact is directly related with numerous extensions and repairs of much damage of the neoplastic cell membranes. Finally, the large medullary tumors (showing many atypic mitosis in glandular neoplastic C cell-type) are deeply penetrated by extensive and irregular vegetative nervous fibers.

[The endocrine pancreas in Varanus niloticus: ultrastructural and cytochemical electron microscopic study and X-ray microdiffraction]. / Le pancréas endocrine de Varanus niloticus: etude ultrastructurale et cytochimique en microscopie électronique et microdiffraction aux rayons X

Electron microscopy has confirmed that there are B and A1 insular cells in the Varanidae; nevertheless, the majority of cells are A2. It is the transformation of canalicular and acinar cells that is responsible for insular regeneration. Mixed cell type can be found very frequently. X Ray microdiffraction has shown that the beta granules contain high levels of zinc; similar concentrations are found in peri-insular exocrine cells. Seasonal sexual activity intensifies the process of exo-endocrine cellular transformation and increases both the zinc level in B and pre-B cells and the sulphur level in A2 cells.