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Biomedical subjects

A M Caille

Publications and source records attributed to A M Caille.

4 recordsLinked to original sources

Modulation of human sperm function by follicular fluid.

Human follicular fluid (hFF), present in the ampullary environment, can reduce the number of sperm bound to the zona pellucida. The aim of the present study was to investigate the effects of follicular fluid on sperm function. The presence of 50% v/v follicular fluid resulted in a significant reduction in the number of bound spermatozoa with respect to control medium (12.7 +/- 5.5 sp HZ(-1) versus 24.6 +/- 5.7 sp HZ(-1), P = 0.03) as measured by the hemizona binding assay. This reduction in zona binding capacity was not associated with a loss of sperm viability, motility or a premature acrosomal reaction. When capacitated spermatozoa were previously exposed 1 h to follicular fluid, a significant reduction in the number of alpha-d-mannose binding sites on sperm head was detected (23.7 +/- 3.1% versus 15.5 +/- 2.4%, P < 0.05). In addition, sperm fertilizing capacity (assessed as the acrosome reaction to ionophore challenge score) in the presence of follicular fluid was also diminished (38.0 +/- 4.8% versus 22.6 +/- 4.9%, P < 0.01). No modification in the pattern of protein tyrosine phosphorylation which occurs during capacitation was observed in the presence of the fluid. Taken together, the results indicate that the decrease in sperm zona-binding capacity observed in the presence of hFF was related to a lower number of sperm containing alpha-d-mannose receptors.

Acrosome Reaction↗

Relationship between antisperm antibodies, sperm movement, and semen quality.

The presence of antisperm antibodies might impair fertilization by affecting sperm function in different ways. The aim of this study was to analyze the incidence of antisperm antibodies and evaluate its impact on sperm movement, in normozoospermic and abnormal semen samples. Samples from 144 patients were classified as normozoospermic or abnormal, according to WHO guidelines and Kruger's strict criteria. Motilility was assessed by a computer-assisted system by placing a drop of semen in a Makler chamber. Antisperm antibodies were detected using the Mar Test and Immunobead tests to identify immunoglobulin location and isotype. Results showed no association between the presence of antisperm antibodies and semen quality. Antibody incidence was 15 and 9.5% for normozoospermic and abnormal semen samples, respectively. Motion analysis showed that, although sperm linearity was significantly reduced in abnormal patients with antibodies, the existence of an immune response did not affect the sperm pathway in most cases. This study suggests that sperm motion analysis would not be of great assistance in the screening of an immunological male fertility factor.

Adult↗

Cerebral metastasis--a study of computerized tomography.

Sixty-eight cases of metastases affecting 34 patients were studied by computerized tomography (CT) before and after the injection of an iodinated contrast medium. CT data provided a diagnosis in most cases. After injection of the contrast medium, a ring aspect was found in half the cases. This morphological feature is a sign of blood-brain barrier impairment crossed by the contrast medium. The low density area inside the ring is not caused by central necrosis, nor is it caused by too little contrast medium. The increase in density is a sign of extra-vascular loss of iodinated molecules in the peritumoral cerebral tissue. Performance of CT should be improved using specific tracers of the tumoral cells.

Brain Neoplasms↗

Does the hypoosmotic swelling test predict human sperm viability?

Human sperm viability is essential for successful fertilization. Eosin Y is the usually accepted method for sperm viability assessment, though the hypoosmotic swelling test has been proposed for the selection of viable spermatozoa in procedures such as intracytoplasmic sperm injection. The present study was designed to determine the value of hypoosmotic swelling test in the prediction of sperm viability. For this purpose, hypoosmotic swelling and eosin Y were performed in parallel and in combination, on both fresh and freeze-thawed semen. Rates for eosin Y were significantly higher than for the hypoosmotic swelling test in fresh semen, with a weak, though significant correlation between the two tests (r = 0.47, p < 0.05). When both tests were performed in succession (hypoosmotic swelling test followed by eosin Y), 14.6% of swollen sperm incorporated the dye. Following exposure to hypoosmotic conditions, sperm viability decreased by 35%. When sperm were killed by freezing, hypoosmotic swelling test rates were higher than eosin Y. Results indicate that these two tests cannot be used interchangeably, since 15% of the swollen sperm apparently died, suggesting that plasma membrane integrity is lost before the capacity to maintain osmotic equilibrium.

Freezing↗