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Biomedical subjects

S Marina

Publications and source records attributed to S Marina.

34 records · Page 2Linked to original sources

Meiotic and synaptonemal complex studies in 45 subfertile males.

We describe the results of meiotic and synaptonemal complex (SC) studies in a selected series of 45 subfertile males with different meiotic and seminal alterations. SC anomalies (pairing anomalies, fragmented SCs, or presynaptic arrest) were observed in 32 cases (71.1%). In 31% of the abnormal cases, meiotic anomalies could only be detected through the study of SCs. The origin of synaptic anomalies may be related to the assembly of myosin molecules along the chromosomes. SC analysis should become routine in the study of subfertile males.

Biopsy↗

Meiotic and synaptonemal complex studies in a 14/21 translocation carrier.

Meiotic studies in a sterile carrier of a 14/21 translocation showed a meiotic arrest, with degeneration of primary spermatocytes. Silver staining of pachytene cells revealed the presence of a trivalent. Its synaptonemal complex was quite similar to that described in previous light and electron microscopy studied in mammalian species. The observation of a trivalent with pairing in trans-configuration and the presence of desynaptic synaptonemal complexes in early pachytene could explain the relatively high incidence of non-disjunction in human D/G translocations and the spermatogenic disintegration sometimes seen in these cases.

Adult↗

Meiotic behaviour of two human reciprocal translocations.

The meiotic behaviour of two male human reciprocal translocations is described. One patient had an unbalanced son and a chain configuration. The second had a stillborn child and a ring corresponding to an adjacent I segregation. The meiotic behaviour of chromosomal rearrangements must be investigated for proper genetic counselling.

Adult↗

[Polyorchidism (author's transl)].

The authors describe two new cases of polyorchidism. In the first case, they removed a testis which had a better seminal line than the testis preserved. In the other case, a conservative attitude was adopted. A review of the literature is followed by a discussion of the benefits of conservative therapy.

Adolescent↗

Balanced translocation (10;13) in a father, ascertained through the study of meiosis in semen, and partial trisomy 10q in his son. Characterization of the region responsible for the partial trisomy 10q syndrome.

We describe a reciprocal translocation (10;13) in a man, ascertained through the study of meiosis in semen, and a partial trisomy 10q in his abnormal son. The phenotypic anomalies of the partial 10q trisomy syndrome are probably due to the presence in triplicate of the region q25 = to qter of chromosome 10.

Abnormalities, Multiple↗

Meiotic studies in human semen. Report of 180 cases.

Meiotic studies can be carried out in the spermatogenic cells present in ejaculate. Using this technique, we identified one man with a reciprocal translocation and six oligochiasmatic males among 180 patients studied. The technique is easy and reliable; good-quality figures can be obtained, and meiotic studies can be carried out as often as needed.

Biopsy↗

Mosaicism in XX males.

Three males with a 46,XX karyotype are described. In two of them, evidence of a Y-containing line was found. In the first case, 1 of 500 lymphocyte metaphases was 48,XXY. In the second, 1 of 400 oral mucosa cells contained a Y body. The proportion of low-grade XX/XXY mosaics found among XX males now stands at about 17%.

Humans↗

Three cases of low chiasma frequency associated with infertility in man.

Three new cases of low chiasma frequency in infertile men are described. In the first case, all cells showed abnormal diakineses; in the second, 20% of the diakineses were desynaptic, while the remaining 80% were normal; in the third, all diakineses were desynaptic and showed chromosome fragmentation. The possible mechanisms leading to asynapsis, desynapsis or precocious chiasma terminalization are discussed.

Adult↗

Cephalexin concentration in the human ejaculate following oral and parenteral administration.

Cephalexin levels in the ejaculates of 31 infection-free volunteers have been determined following the administration of 1 g of antibiotic. In 16 subjects the cephalexin was administered by intramuscular injection and in 15 by mouth. In each case the volunteers were divided into groups of five each of which received the drug, 1, 2 or 4 hours before the collection of semen. Antibiotic concentrations were determined microbiologically on agar plates using Sarcina lutea ATCC 9341. For selection purposes healthy subjects were considered to be those showing a normal anamnesis and physical exploration, an absence of leucocytes demonstrable by a cytomorphological evaluation of the semen, semen citric acid and fructose levels within normal limits and a qualitatively and quantitatively similar saprophytic flora to that seen in a culture of urine taken immediately before the collection of semen. Maximum concentrations were obtained 2 hours after the administration of the antibiotic and the concentration following intramuscular injection (6.9 microgram/ml) was significantly greater than that following oral administration (4.7 microgram/ml).

Administration, Oral↗