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Biomedical subjects

L Blasco

Publications and source records attributed to L Blasco.

61 records · Page 4Linked to original sources

Spontaneous lipid peroxidation and production of hydrogen peroxide and superoxide in human spermatozoa. Superoxide dismutase as major enzyme protectant against oxygen toxicity.

Spontaneous lipid peroxidation in washed human spermatozoa was induced by aerobic incubation at 32 C and measured by malonaldehyde production; loss of motility during the incubation was determined simultaneously. Malonaldehyde production at the point of complete loss of motility, defined as the lipoperoxidative lethal endpoint (LLE), was 0.10 +/- 0.03 nmol/10(8) cells (mean +/- SD, n = 40), and was independent of the time to complete loss of motility. Human spermatozoa produced both H2O2 and O2-. during aerobic incubation. Inhibition of superoxide dismutase in these cells with KCN showed that all the H2O2 production is due to action of the dismutase. The superoxide dismutase activity of individual human sperm samples varied between 1 and 10 U/10(8) cells, variations between samples from a single donor being nearly as great as those between different donors. The time to complete motility loss (tL) showed equal variation of 1 to 10 hours among samples. The rate of spontaneous lipid peroxidation, calculated as LLE/tL, for a given sperm sample and the superoxide dismutase activity of the same sample, determined prior to aerobic incubation, gave a good linear correlation (r = 0.97). Glutathione reductase, glutathione peroxidase, and glutathione were found to be present in human spermatozoa, but showed little variation among samples. These results suggest that superoxide dismutase plays the major role in protecting human spermatozoa against lipid peroxidation. In addition, the superoxide dismutase activity of a fresh sperm sample appears to be a good predictor of the lifetime (up to the complete loss of motility) of that particular sample, and so may prove useful in semen analysis.

Humans↗

Human in vitro fertilization.

Human in vitro fertilization has become a widely accepted method of treatment for infertile couples. The list of indications for this technique is rapidly growing and includes oligospermia, endometriosis, and unexplained infertility. The techniques of follicular recruitment, ovum maturation, and follicular aspiration, as well as laboratory culture techniques, are described. The various factors to be taken into consideration when trying to assess possible success of in vitro fertilization and embryo transfer are discussed in this paper.

Chorionic Gonadotropin↗

Assessment of the cause of infertility.

The different causes of infertility and evaluation of the infertile couple are reviewed in this paper. Forty to 50 percent of cases are due to male factors, and special emphasis is placed in describing techniques to diagnosis this type of infertility. Five to ten percent of infertile couples have infertility of unknown etiology even after a complete, appropriate evaluation. Special instruction in how to diagnose and treat these types of patients is described. A step by step evaluation of peritoneal factors, ovulation factors, and male and cervical mucus interaction is presented for the clinicians' use.

Cervix Mucus↗