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Biomedical subjects

F Vidal

Publications and source records attributed to F Vidal.

At least 253 records · Page 14Linked to original sources

Meiotic studies and synaptonemal complex analysis in two infertile males with a 13/14 balanced translocation.

Meiotic and synaptonemal complex studies by light and electron microscopy have been carried out in two infertile males with a balanced 13/14 translocation. As expected, all metaphase I figures in conventional meiotic preparations contained a chain trivalent. Synaptonemal complex studies showed typical trivalent images with incomplete pairing of the acrocentric elements in the cis configuration. A review of the literature shows that the fertility of these patients is quite variable. All of them show a slightly reduced number of chiasmata (mean 46.6). Pairing in cis, as detected by electron microscopic studies, does not seem to have a prognostic value.

Adult↗

Development and behavior of synaptonemal complexes in human spermatocytes by light and electron microscopy.

We describe in this paper the human male synaptic cycle using light and electron microscopy and the distribution of cells in the different stages of prophase I. The pattern of chromosome pairing and synapsis is an important tool to determine accurately whether a given synaptic behavior in infertile or sterile men is really abnormal or not. The relationship of prepachytene to pachytene cells is also important for the diagnosis of the different types of meiotic arrest at the primary spermatocyte level.

Cell Nucleus↗

Synaptonemal complex studies in a mosaic 46,XY/47,XXY male.

We describe the results of synaptonemal complex (SCs) studies by light (LM) and electron microscopy (EM) in a sterile 46,XY/47,XXY male mosaic. Meiotic studies showed an arrest at the first spermatocyte level. Pachytene figures showed three types of cells: (1) cells with normal SCs, normal sex vesicle, and a 23,XY constitution; (2) cells with no sex vesicle, normal pairing of SCs, and a 24, (?) constitution; and (3) cells with a normal sex vesicle and fragmented SCs.

Adult↗

Meiotic studies in a series of 1100 infertile and sterile males.

Meiotic studies have been carried out in a series of 1100 infertile and sterile males. Of these, 599 cases have been studied in testicular biopsy, and 501, in semen samples. This is the largest meiotic series published so far. The incidence of meiotic anomalies was 4.3%. The most frequent chromosome abnormality was desynapsis (3.7%). However, the number of cases with a meiotic arrest, usually due (73.9%) to synaptic anomalies in prophase I, was much higher (18.4%). An attempt is made to correlate the incidence of meiotic anomalies with the results of semen analysis. We discuss the prognosis of desynapsis, based on 41 cases studied, and reevaluate the results obtained in semen samples as compared with our previous results.

Chromosome Aberrations↗