Biomedical subjects
Publications and source records attributed to S Warter.
Human semen in two chromosomal abnormalitie cases presents one important increase of small, large and double head spermatozoa. Findings of this type of abnormal sperm morphology must be include chromosome analysis in the subfertile couple investigations.
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Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The DNA content of different human spermatozoa morphological types was measured by cytospectrophotometry in 10 fertile subjects. The level of DNA varied with morphological type. Duplicated spermatozoa heads contained twice the DNA content of normal spermatozoa, while macrocephalic spermatozoa DNA content was situated between these two (haploid and diploid) levels. These results led to the conclusion that morphological abnormalities in spermatozoa seem to be the consequence of chromosomal non-disjunction during meiosis.
A relationship exists between several semen parameters and the ability of spermatozoa to capacitate. The increase of oligoteratozoospermia, which could be related to testicular dysfunction, is correlated with the decrease of the percentage of spermatozoa able to "capacitate". The increase of loss of motility with time, which could be related to abnormalities of the seminal fluid, is also correlated with a decreased number of spermatozoa able to "capacitate".
Cytogenetic investigations performed on 30 specimens of Lepilemur septentrionalis confirmed the existence of 4 karyotypes differing from each other by 1-2 chromosomal rearrangements. These data, pooled with those obtained in earlier studies, showed that out of 60 animals karyotyped only two kinds of hybrids were detected, allowing us to characterise two chromosomally polymorphic populations. No natural hybrids could be found between these two populations, which could thus be considered as two separate species. The possible role of the chromosomal rearrangements in the process of reproductive isolation between these two populations is discussed.
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