Objective: To evaluate sperm DNA fragmentation and semen parameters to diagnose male factor infertility and predict pregnancy after IVF.
Design: Prospective study.
Setting: Academic research laboratory.
Background: Sperm DNA damage shows great promise as a biomarker of infertility. The study aim is to determine the usefulness of DNA fragmentation (DF), including modified bases (MB), to predict assisted reproduction treatment (ART) outcomes.
Methods: DF in 360 couples (230 IVF and 130 ICSI) was measured by the alkaline Comet assay in semen and in sperm following density gradient centrifugation (DGC) and compared with fertilization rate (FR), embryo cumulative scores (ECS(1)) for the total number of embryos/treatment, embryos transferred (ECS(2)), clinical pregnancy (CP) and spontaneous pregnancy loss.
DNA fragmentation in testicular sperm from men with obstructive azoospermia is increased by 4-hour and 24-hour incubations and after cryopreservation with the effect is intensified by post-thaw incubation. Testicular sperm for use in intracytoplasmic sperm injection (ICSI) should be injected without delay.
View Article and Find Full Text PDFThe survival and growth of populations of the obligately anaerobic pathogenic bacterium Bacteroides fragilis enriched for large capsules (LCs), small capsules (SCs) or an electron-dense layer (EDL; non-capsulate by light microscopy) were examined in a mouse model of infection over a minimum period of 20 d. Chambers which allowed the influx of leukocytes, but not the efflux of bacteria, were implanted in the mouse peritoneal cavity. The LC and EDL populations consistently attained viable cell densities of the order of 10(8)-10(9) c.
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