BoviPure® density-gradient centrifugation procedure enhances the quality of fresh and cryopreserved dog epididymal spermatozoa.

BoviPure® is a salt solution containing colloidal silica particles coated with silane used to select sperm (e.g., ruminants) by density-gradient centrifugation (DGC). This research assessed the suitability of the BoviPure-DGC and swim-up methods for selecting dog epididymal sperm in fresh, chilled and frozen-thawed samples on post-treatment sperm quality. Sperm samples (n = 60 epididymides) were recovered by retrograde flushing from thirty orchiectomized adult dogs. Thereafter, 20 sperm pools, containing sperm aliquots of three randomly selected animals, were used for chilling (at 5 ºC for 24 h) and freezing (in liquid nitrogen vapors). Sperm selection by BoviPure-DCG and swim-up was performed in both individual and pooled samples, including non-selected samples as controls. Overall, after BoviPure-DGC selection a higher sperm retrieval rate was obtained than the swim-up selection in both individual (P < 0.05) and pooled (P < 0.01) samples. BoviPure-DGC improved (P < 0.05) the total (TM) and progressive (PSM) sperm motilities, curvilinear (VCL) and straight-line (VSL) velocities, linearity (LIN), wobble (WOB), beat-cross frequency (BCF), and integrity of plasmatic (IPM) and acrosomal (IAM) membranes of individual samples in comparison with non-selected samples. In pooled samples, however, the BoviPure-DGC improved (P < 0.05) the PSM, VCL, WOB, and IPM of chilled and frozen-thawed samples. The swim-up method improved (P < 0.05) only some kinematic variables of the individual (VCL, WOB and BCF) and cryopreserved pooled samples (VCL and ALH) in comparison with non-selected samples. In conclusion, BoviPure-DGC was more effective for recovering and selecting both fresh and cryopreserved dog epididymal sperm than the swim-up procedure improving the kinematic variables, and membranes intactness.

Gunshot wounds: bullet caliber is increasing.

BACKGROUND: The incidence of gunshot wounds has increased over the past two decades. In the past several years at our Level I trauma center in Newark NJ, we perceived that the size of ammunition involved in these wounds has been increasing as well. We sought to document this trend by using autopsy data as well as bullets received by surgical pathology. METHODS: Measurements of bullets stored in surgical pathology were taken from alternate years between 1981 and 1993, then every year through 1997. A total of 745 bullets were studied in this 16-year period. Bullets deformed beyond measurability and shotgun pellets were excluded from the study (approximately 20%). Linear regression of mean bullet caliber over time was performed, and analysis of variance was used to assess statistical significance of apparent differences. In addition, autopsy reports from the regional medical examiner's office were surveyed for description of bullet size. Bullet caliber, in these reports, is described as "small," "medium," or "large." A total of 397 reports were studied from 1981 to 1997. Once again, shotgun wounds (<5%) were excluded. The percentage of large-caliber projectiles was plotted against time, and chi2 for trend was used to determine statistical significance. RESULTS: Results are tabulated as mean +/- standard error bullet caliber (millimeters) over time. Linear regression reveals r = 0.944, p<0.0001. Data obtained from autopsy reports are not tabulated here, but chi2 for trend reveals a statistically significant increase in the proportion of large caliber and decrease in proportion of small-caliber bullets (p<0.001). CONCLUSION: These data unveil an ominous trend toward the use of larger-caliber firearms in accidents, homicides, and suicides.