Semen

About: Semen is a research topic. Over the lifetime, 14571 publications have been published within this topic receiving 407739 citations. The topic is also known as: come & ejaculate.

Cryopreservation of human semen. Comparison of cryopreservatives, sources of variability, and prediction of post-thaw survival.

Abstract: Human semen was cryopreserved using Human Sperm Preservation Medium, TEST-Yolk buffer, or glycerol alone. Sperm characteristics for each specimen were measured before and after freezing to determine which cryopreservative resulted in better cryosurvival and recovery of motile sperm. Sperm frozen in Human Sperm Preservation Medium had a sig- nificantly better recovery of all semen parameters (motility, ye- locity, and recovery) than either TEST-Yolk or glycerol alone. Statistical analyses also were done to examine the variability between and within donor semen specimens. Differences be- tween donors, between specimens, and measurements within donors all contributed to variability of sperm characteristics. Specimen-to-specimen variability for a given donor represented 12% to 47% of the total variability, whereas processing and mea- surementvariability represented 12% to 41%. Donors also varied in the ability of their sperm to tolerate freezing. There was a relationship between motile count after dilution with cryopreser- vative and post-thaw motile count. This relationship allows the prediction of poor-thaw survival before freezing a specimen.

Some chemical and physical characteristics of the semen of Cyprinus carpio L. and Oreochromis mossambicus (Peters)

Abstract: The chemical and physical characteristics of the semen of Cyprinus carpio and Oreochromis mossambicus were investigated on a comparative and seasonal basis. Results were obtained for the volume, colour and viscosity of the semen, the percentage live spermatozoa, sperm concentrations and the degree and the duration of sperm motility under different environmental conditions. All showed distinct interspecific and less conspicuous seasonal intraspecific differences. Values have also been determined for the organic and inorganic components and the pH and osmolality of the seminal fluid. Some inorganic and organic components indicated seasonal intraspecific differences while all the components, with the exception of sodium and galactose, indicated significant interspecific differences. These observations suggest significant interspecific differences in the testicular secretions of the two fish species which add to the basic physiological differences recorded for the spermatozoa of C. carpio and O. mossambicus. The probable function of the carbohydrates, protein and enzymes present in the semen of these fish species are discussed.

Exposure to environmental ozone alters semen quality.

Abstract: Idiopathic male infertility may be due to exposure to environmental toxicants that alter spermatogenesis or sperm function. We studied the relationship between air pollutant levels and semen quality over a 2-year period in Los Angeles, California, by analyzing repeated semen samples collected by sperm donors. Semen analysis data derived from 5,134 semen samples from a sperm donor bank were correlated with air pollutant levels (ozone, nitrogen dioxide, carbon monoxide, and particulate matter < 10 microm in aerodynamic diameter) measured 0-9, 10-14, and 70-90 days before semen collection dates in Los Angeles between January 1996 and December 1998. A linear mixed-effects model was used to model average sperm concentration and total motile sperm count for the donation from each subject. Changes were analyzed in relationship to biologically relevant time points during spermatogenesis, 0-9, 10-14, and 70-90 days before the day of semen collection. We estimated temperature and seasonality effects after adjusting for a base model, which included donor's date of birth and age at donation. Forty-eight donors from Los Angeles were included as subjects. Donors were included if they collected repeated semen samples over a 12-month period between January 1996 and December 1998. There was a significant negative correlation between ozone levels at 0-9, 10-14, and 70-90 days before donation and average sperm concentration, which was maintained after correction for donor's birth date, age at donation, temperature, and seasonality (p < 0.01). No other pollutant measures were significantly associated with sperm quality outcomes. Exposure to ambient ozone levels adversely affects semen quality.

Distribution of the receptor for advanced glycation end products in the human male reproductive tract: prevalence in men with diabetes mellitus

Abstract: BACKGROUND: Diabetics have a significantly higher percentage of sperm with nuclear DNA (nDNA) fragmentation and increased levels of advanced glycation end products (AGEs), in their testis, epididymis and sperm. As the receptor for AGEs (RAGE) is important to oxidative stress and cell dysfunction, we hypothesise, that it may be involved in sperm nDNA damage. METHODS: Immunohistochemistry was performed to determine the presence of RAGE in the human testis and epididymis. A comparison of the receptor's incidence and localization on sperm from 10 diabetic and 11 non-diabetic men was conducted by blind semi-quantitative assessment of the immunostaining. Enzyme-linked immunosorbent assay analysis ascertained RAGE levels in seminal plasma and sperm from 21 diabetic and 31 non-diabetic subjects. Dual labelling immunolocalization was employed to evaluate RAGE's precise location on the sperm head. RESULTS: RAGE was found throughout the testis, caput epididymis, particularly the principle cells apical region, and on sperm acrosomes. The number of sperm displaying RAGE and the overall protein amount found in sperm and seminal plasma were significantly higher in samples from diabetic men (P < 0.01, P < 0.0001 and P < 0.0001, respectively). CONCLUSIONS: The presence of RAGE implies that it may play a central role in sperm nDNA damage particularly in diabetic men where the levels are elevated.

Aluminium, lead and cadmium concentrations in seminal plasma and spermatozoa, and semen quality in Finnish men.

Abstract: Aluminium, cadmium and lead concentrations in the spermatozoa and seminal plasma of 27 employees of two industrial companies, a refinery and a polyolefin factory, and 45 consecutive sperm donor candidates at a sperm bank were studied using atomic absorption measurements. The relationship between metal concentration and parameters of semen analysis was studied. A high concentration of aluminium in spermatozoa was correlated with decreased sperm motility. The concentrations of cadmium and lead were low and did not show any correlation with parameters of semen analysis. Aluminium may be one of the environmental pollutants causing impaired semen quality. The mean sperm concentrations were similar in the factory employees (96 x 10 6 /ml), in the sperm donor candidates of the comparison group (104 x 10 6 /ml) and in 352 donor candidates at the sperm bank of the Family Federation of Finland (107 x 10 6 /ml) between May 1993 and May 1995.