A computerized image analysis system was used to determine the SCGE tail moment of the nuclei as an index of DNA damage.The digitalized data were automatically transferred to a computerbased spreadsheet for subsequent statistical analysis.The microgel, and not the nucleus, is the unit of measure.We follow this procedure to reduce the possibility of type statistical errors.We analyze nuclei per microgel, and with these data, we determined the median SCGE tail moment value.These median values are averaged and used for our statistical analysis.For each treatment group, we analyzed at least eight microgels.After the treatment, the microgels were dipped twice in water and placed in an alkaline buffer, and the protocol was continued as described above.The cell suspension was mixed with an equal volume of low melting point agarose prepared with PBS, and two AL aliquots were placed on the same SCGE microscope slides described previously, making two microgels per slide.A second layer of low melting point agarose was not applied in this case.Detailed methods for preparing the slides were published previously. The microgels were kept in lysing solution at jC overnight, washed, and treated.The microgels were incubated for min at jC, and then the reaction was stopped by placing the slides on a tray with ice for min.The microgels were processed for electrophoresis and microscopic analysis of the nuclei.At least three independent experiments were conducted with eight microgels analyzed per treatment group.The median SCGE tail moment value for each microgel was determined, and the data from all of the microgels representing each treatment concentration were averaged.Averaged median values express a normal distribution according to the central limit theorem and were used with a oneway ANOVA test. Metabolism of dietary sulphate: absorption and excretion in humans.Incidence and activities of sulphatereducing bacteria in patients with ulcerative colitis.The contribution of sulphate reducing bacteria and aminosalicylic acid to faecal sulphide in patients with ulcerative colitis.Statistics for experimenters: an introduction to design, data analysis and model building.Published OnlineFirst May; DOI. Click on Request Permissions which will take you to the Copyright Clearance Centers Downloaded from mcr.aacrjournals.org on September. American Association for Cancer Research. In this review, we outline our current understanding of how sperm DNA is organized, what causes sperm DNA damage, what impact this damage may have on reproductive capacity and whether tests of sperm DNA damage are clinically useful.S emen analysis is the cornerstone of the evaluation of infertile men.Semen volume and pH level are an index of seminal vesicle and prostate function.Sperm concentration, motility and morphology are largely determined by testicular function and, to a lesser extent, by posttesticular genital tract function.Although fertile men as a group have higher mean sperm parameters than do infertile men, there is significant overlap between these groups.Moreover, these factors are generally modest predictors of reproductive outcomes.The study of sperm DNA damage is particularly relevant in an era where advanced forms of assisted reproductive technologies are frequently used.Fertilization involves the direct interaction of the sperm and oocyte, fusion of the cell membranes and union of male and female gamete genomes.